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Tulkens D, Boelens M, Naert T, Carron M, Demuynck S, Dewaele S, Van Isterdael G, Creytens D, Pieters T, Goossens S, Van Vlierberghe P, Vleminckx K. Mutations in the histone methyltransferase Ezh2 drive context-dependent leukemia in Xenopus tropicalis. Leukemia 2023; 37:2404-2413. [PMID: 37794102 DOI: 10.1038/s41375-023-02052-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/06/2023]
Abstract
CRISPR-mediated simultaneous targeting of candidate tumor suppressor genes in Xenopus tropicalis allows fast functional assessment of co-driver genes for various solid tumors. Genotyping of tumors that emerge in the mosaic mutant animals rapidly exposes the gene mutations under positive selection for tumor establishment. However, applying this simple approach to the blood lineage has not been attempted. Multiple hematologic malignancies have mutations in EZH2, encoding the catalytic subunit of the Polycomb Repressive Complex 2. Interestingly, EZH2 can act as an oncogene or a tumor suppressor, depending on cellular context and disease stage. We show here that mosaic CRISPR/Cas9 mediated ezh2 disruption in the blood lineage resulted in early and penetrant acute myeloid leukemia (AML) induction. While animals were co-targeted with an sgRNA that induces notch1 gain-of-function mutations, sequencing of leukemias revealed positive selection towards biallelic ezh2 mutations regardless of notch1 mutational status. Co-targeting dnm2, recurrently mutated in T/ETP-ALL, induced a switch from myeloid towards acute T-cell leukemia. Both myeloid and T-cell leukemias engrafted in immunocompromised hosts. These data underline the potential of Xenopus tropicalis for modeling human leukemia, where mosaic gene disruption, combined with deep amplicon sequencing of the targeted genomic regions, can rapidly and efficiently expose co-operating driver gene mutations.
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Affiliation(s)
- Dieter Tulkens
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Marthe Boelens
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Thomas Naert
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Marjolein Carron
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Center for Medical Genetics, Ghent University, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Suzan Demuynck
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Sylviane Dewaele
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- VIB Center for Inflammation Research, Ghent, Belgium
| | - Gert Van Isterdael
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- VIB Flow Core, VIB Center for Inflammation Research, Ghent, Belgium
| | - David Creytens
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
- Department of Pathology, Ghent University and Ghent University Hospital, Ghent, Belgium
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Tim Pieters
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
- Center for Medical Genetics, Ghent University, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Steven Goossens
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Pieter Van Vlierberghe
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
- Center for Medical Genetics, Ghent University, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Kris Vleminckx
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
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2
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Carlet M, Schmelz K, Vergalli J, Herold T, Senft D, Jurinovic V, Hoffmann T, Proba J, Weichert N, Junghanß C, Roth M, Eschenburg G, Barz M, Henze G, Eckert C, Eggert A, Zuber J, Hundsdoerfer P, Jeremias I. X-linked inhibitor of apoptosis protein represents a promising therapeutic target for relapsed/refractory ALL. EMBO Mol Med 2022; 15:e14557. [PMID: 36416169 PMCID: PMC9832863 DOI: 10.15252/emmm.202114557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 10/23/2022] [Accepted: 10/28/2022] [Indexed: 11/25/2022] Open
Abstract
Acute lymphoblastic leukemia (ALL) represents the most frequent malignancy in children, and relapse/refractory (r/r) disease is difficult to treat, both in children and adults. In search for novel treatment options against r/r ALL, we studied inhibitor of apoptosis proteins (IAP) and Smac mimetics (SM). SM-sensitized r/r ALL cells towards conventional chemotherapy, even upon resistance against SM alone. The combination of SM and chemotherapy-induced cell death via caspases and PARP, but independent from cIAP-1/2, RIPK1, TNFα or NF-κB. Instead, XIAP was identified to mediate SM effects. Molecular manipulation of XIAP in vivo using microRNA-30 flanked shRNA expression in cell lines and patient-derived xenograft (PDX) models of r/r ALL mimicked SM effects and intermediate XIAP knockdown-sensitized r/r ALL cells towards chemotherapy-induced apoptosis. Interestingly, upon strong XIAP knockdown, PDX r/r ALL cells were outcompeted in vivo, even in the absence of chemotherapy. Our results indicate a yet unknown essential function of XIAP in r/r ALL and reveal XIAP as a promising therapeutic target for r/r ALL.
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Affiliation(s)
- Michela Carlet
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany,Department of Biotechnology and Food EngineeringMCI, The Entrepreneur SchoolInnsbruckAustria
| | - Karin Schmelz
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany,German Cancer Consortium (DKTK)BerlinGermany
| | - Jenny Vergalli
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany
| | - Tobias Herold
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany,Laboratory for Leukemia Diagnostics, Department of Medicine IIIUniversity Hospital, LMU MunichMunichGermany,German Cancer Consortium (DKTK), Partnering Site MunichMunichGermany
| | - Daniela Senft
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany
| | - Vindi Jurinovic
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany,Laboratory for Leukemia Diagnostics, Department of Medicine IIIUniversity Hospital, LMU MunichMunichGermany,Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMUMunichGermany
| | - Thomas Hoffmann
- Research Institute of Molecular Pathology (IMP)ViennaAustria
| | - Jutta Proba
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany
| | - Nina Weichert
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany
| | - Christian Junghanß
- Department of Medicine, Clinic III – Hematology, Oncology, Palliative MedicineRostock University Medical CenterRostockGermany
| | - Mareike Roth
- Research Institute of Molecular Pathology (IMP)ViennaAustria
| | - Georg Eschenburg
- Department of Pediatric SurgeryUniversity Medical Center Hamburg‐EppendorfHamburgGermany
| | - Malwine Barz
- University Children's Hospital ZurichZurichSwitzerland
| | - Günter Henze
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany
| | - Cornelia Eckert
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany
| | - Angelika Eggert
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany
| | - Johannes Zuber
- Research Institute of Molecular Pathology (IMP)ViennaAustria
| | - Patrick Hundsdoerfer
- Department of Pediatric Oncology/HematologyCharité‐UniversitätsmedizinBerlinGermany,Berlin Institute of HealthBerlinGermany,Department of PediatricsHelios Klinikum Berlin‐BuchBerlinGermany
| | - Irmela Jeremias
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Zentrum MünchenGerman Center for Environmental Health (HMGU)MunichGermany,German Cancer Consortium (DKTK), Partnering Site MunichMunichGermany,Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMUMunichGermany
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Liu J, Yang L, Liu X, Liu L, Liu M, Feng X, Luo J. lncRNA HOTTIP Recruits EZH2 to Inhibit PTEN Expression and Participates in IM Resistance in Chronic Myeloid Leukemia. Stem Cells Int 2022; 2022:9993393. [PMID: 36117724 PMCID: PMC9477575 DOI: 10.1155/2022/9993393] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/29/2022] [Accepted: 08/10/2022] [Indexed: 11/18/2022] Open
Abstract
Objective To investigate that HOTTIP suppressed PTEN gene expression and was involved in IM resistance in chronic myeloid leukemia through recruitment of EZH2 protein. Methods Seventy-one cases of bone marrow monocytes diagnosed with CML in the Second Hospital of Hebei Medical University from 2018 to 2021 were selected. These patients were diagnosed with CML by bone marrow morphology, immunology, molecular biology, and cytogenetics, of which 36 were sensitive to IM and 35 were resistant to IM. We selected K562 and IR-K562 cells preserved in the laboratory as our subjects to study the expression levels of HOTTIP in the bone marrow cells of IM CML-resistant patients and IM-resistant cells. Results In this study, we found that HOTTIP was highly expressed in the bone marrow and cell lines of CML patients resistant to Imatinib mesylate (IM). In in vitro experiments, lentiviral knockdown of HOTTIP inhibited CML cell proliferation and promoted apoptosis, and knockdown of HOTTIP also increased sensitivity to IM. Mechanistically, highly expressed HOTTIP is involved in the biological process of IM resistance by recruiting Zeste homologous protein 2 enhancer (EZH2) to inhibit the expression of phosphatase and Tensin homologous protein (PTEN) genes. Conclusions We confirmed that HOTTIP and EZH2 are highly expressed in IM-resistant patients and IM-resistant CML cell lines. In CML cell lines, HOTTIP is involved in regulating the proliferation and apoptosis of CML cells and resistance to IM.
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Affiliation(s)
- Jing Liu
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Lin Yang
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Xiaojun Liu
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Lu Liu
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Menghan Liu
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Xuefeng Feng
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Jianmin Luo
- Key Laboratory of Hematology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
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Liu QH, Dai GR, Wang XN, Wang L, Li LL, Wu ZS, Xia RX. CDK12 activates MYC to repress miR-28-5p/EZH2 and amplifies tonic BCR signaling to promote the development of diffuse large B-cell lymphoma. Cancer Gene Ther 2022; 29:1207-1216. [PMID: 35082399 DOI: 10.1038/s41417-021-00415-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 10/11/2021] [Accepted: 12/03/2021] [Indexed: 11/09/2022]
Abstract
Cyclin-dependent kinase 12 (CDK12) is a transcription-associated kinase that participates in various cellular processes. However, its regulatory role in the progression of diffuse large B-cell lymphoma (DLBCL), which is the most prevalent subtype of non-Hodgkin lymphoma (NHL), is still elusive and controversial.The expression of CDK12 was detected by immunohistochemistry (IHC), RT-qPCR was performed to detect miR-28-5p expression of OCI-LY3 and SU-DHL-4 cells. MTT and soft agarose colony formation assays were used to detect cell proliferation. The cell apoptosis was determined by flow cytometry. The protein expressions changes of MYC, EZH2 and the biomarkers of BCR signaling were also detected. A subcutaneous transplantation tumor model of OCI-LY3 cells in nude mice was established to evaluate anticarcinogenic activities of CDK12 knockdown. Elevated expression of CDK12 was observed while miR-28-5p was downregulated in DLBCL tissues. CDK12 knockdown or miR-28-5p overexpression could inhibit proliferation and promote apoptosis of DLBCL cells. miR-28-5p inhibition could reverse the effect of CDK12 knockdown on proliferation and apoptosis of DLBCL cells. In addition, CDK12 knockdown could inhibit DLBCL tumor growth in the mice model. CDK12 activated MYC to repress miR-28-5p/EZH2 and amplified tonic BCR signaling to promote the development of DLBCL, which might provide potential therapeutic targets for future therapeutic intervention in DLBCL.
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Affiliation(s)
- Qin-Hua Liu
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China
| | - Guan-Rong Dai
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China
| | - Xiao-Nan Wang
- Laboratory of Pathogenic Microbiology and Immunology, Anhui Medical University, Hefei, 230032, Anhui Province, China
| | - Lin Wang
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China
| | - Li-Li Li
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China
| | - Zheng-Sheng Wu
- Department of Pathology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China
| | - Rui-Xiang Xia
- Department of Hematology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, Anhui Province, China.
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Czegle I, Gray AL, Wang M, Liu Y, Wang J, Wappler-Guzzetta EA. Mitochondria and Their Relationship with Common Genetic Abnormalities in Hematologic Malignancies. Life (Basel) 2021; 11:1351. [PMID: 34947882 PMCID: PMC8707674 DOI: 10.3390/life11121351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/29/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022] Open
Abstract
Hematologic malignancies are known to be associated with numerous cytogenetic and molecular genetic changes. In addition to morphology, immunophenotype, cytochemistry and clinical characteristics, these genetic alterations are typically required to diagnose myeloid, lymphoid, and plasma cell neoplasms. According to the current World Health Organization (WHO) Classification of Tumors of Hematopoietic and Lymphoid Tissues, numerous genetic changes are highlighted, often defining a distinct subtype of a disease, or providing prognostic information. This review highlights how these molecular changes can alter mitochondrial bioenergetics, cell death pathways, mitochondrial dynamics and potentially be related to mitochondrial genetic changes. A better understanding of these processes emphasizes potential novel therapies.
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Affiliation(s)
- Ibolya Czegle
- Department of Internal Medicine and Haematology, Semmelweis University, H-1085 Budapest, Hungary;
| | - Austin L. Gray
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA; (A.L.G.); (Y.L.); (J.W.)
| | - Minjing Wang
- Independent Researcher, Diamond Bar, CA 91765, USA;
| | - Yan Liu
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA; (A.L.G.); (Y.L.); (J.W.)
| | - Jun Wang
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA; (A.L.G.); (Y.L.); (J.W.)
| | - Edina A. Wappler-Guzzetta
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA; (A.L.G.); (Y.L.); (J.W.)
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Loss-of-function mutations in the histone methyltransferase EZH2 promote chemotherapy resistance in AML. Sci Rep 2021; 11:5838. [PMID: 33712646 PMCID: PMC7955088 DOI: 10.1038/s41598-021-84708-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/15/2021] [Indexed: 12/25/2022] Open
Abstract
Chemotherapy resistance is the main impediment in the treatment of acute myeloid leukaemia (AML). Despite rapid advances, the various mechanisms inducing resistance development remain to be defined in detail. Here we report that loss-of-function mutations (LOF) in the histone methyltransferase EZH2 have the potential to confer resistance against the chemotherapeutic agent cytarabine. We identify seven distinct EZH2 mutations leading to loss of H3K27 trimethylation via multiple mechanisms. Analysis of matched diagnosis and relapse samples reveal a heterogenous regulation of EZH2 and a loss of EZH2 in 50% of patients. We confirm that loss of EZH2 induces resistance against cytarabine in the cell lines HEK293T and K562 as well as in a patient-derived xenograft model. Proteomics and transcriptomics analysis reveal that resistance is conferred by upregulation of multiple direct and indirect EZH2 target genes that are involved in apoptosis evasion, augmentation of proliferation and alteration of transmembrane transporter function. Our data indicate that loss of EZH2 results in upregulation of its target genes, providing the cell with a selective growth advantage, which mediates chemotherapy resistance.
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Zhong X, Liao Y, Chen X, Mai N, Ouyang C, Chen B, Zhang M, Peng Q, Liang W, Zhang W, Wu Z, Huang X, Li C, Chen H, Lao W, Zhang CE, Wang X, Ning Y, Liu J. Abnormal Serum Bilirubin/Albumin Concentrations in Dementia Patients With Aβ Deposition and the Benefit of Intravenous Albumin Infusion for Alzheimer's Disease Treatment. Front Neurosci 2020; 14:859. [PMID: 33013289 PMCID: PMC7494757 DOI: 10.3389/fnins.2020.00859] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/23/2020] [Indexed: 12/13/2022] Open
Abstract
Background Our previous study in animal models revealed that bilirubin could induce Aβ formation and deposition. Bilirubin may be important in neurodegenerative dementia with Aβ deposition. Hence, lowering the concentration of the free bilirubin capable of crossing the blood brain-barrier may benefit the treatment of Alzheimer's disease (AD). Objectives The objectives of this study were to examine the change in the serum bilirubin and albumin concentrations of dementia patients with Aβ deposition, and to determine the effects of intravenous administration of albumin in the treatment of AD. Methods Bilirubin and albumin concentrations in dementia patients with Aβ deposition were examined. Cell viability and apoptosis were determined in dopaminergic neuron-like cells MN9D treated with bilirubin in the presence of diverse concentrations of serum. Human albumin at a dose of 10 g every 2 weeks for 24 weeks was administered intravenously to AD patients to examine the effect of albumin on AD symptoms. Results Significantly higher indirect bilirubin (IBIL) concentrations, lower albumin concentrations, and higher ratio of IBIL to albumin (IBIL/ALB) were observed in dementia patients with Aβ deposition, including AD, dementia with Lewy bodies, and general paresis of insane. In vitro assays showed that bilirubin-induced injury in cultured dopaminergic neuron-like cells negatively depends on the concentration of serum in the culture medium. General linear model with repeated measures analysis indicated a main effect of group on the change in albumin concentrations and Alzheimer's Disease Cooperative Study Activities of Daily Living Inventory scale (ADCS-ADL) scores, and the main effect of time and group, and group-by-time interaction on the change of Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB) scores. Analysis of the combined data of the entire 28 weeks of assessment period using the area under curve convincingly showed significantly improvements in the change of albumin concentrations, ADCS-ADL scores, and CDR-SB scores. Conclusion IBIL and the IBIL/ALB ratio are significantly higher in dementia patients with Aβ deposition, and intravenous administration of albumin is beneficial to AD treatment. Trial Registration The intervention study was registered at http://www.chictr.org.cn (ChiCTR-IOR-17011539). Date of registration: June 1, 2017.
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Affiliation(s)
- Xiaomei Zhong
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Yuning Liao
- Protein Modification and Degradation Lab, SKLRD, School of Basic Medical Sciences, Affiliated Cancer Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xinru Chen
- Institute of Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Naikeng Mai
- Institute of Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Cong Ouyang
- Institute of Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Ben Chen
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Min Zhang
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Qi Peng
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Wanyuan Liang
- Institute of Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Weiru Zhang
- Institute of Neuroscience, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Zhangying Wu
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Xingxiao Huang
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Caijun Li
- Guangzhou Yihe Nursing Home, Guangzhou, China
| | - Hong Chen
- Guangzhou Yihe Nursing Home, Guangzhou, China
| | - Weimin Lao
- Guangzhou Songhe Nursing Home, Guangzhou, China
| | - Chang-E Zhang
- Protein Modification and Degradation Lab, SKLRD, School of Basic Medical Sciences, Affiliated Cancer Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xuejun Wang
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, United States
| | - Yuping Ning
- Department of Geriatric Psychiatry, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Jinbao Liu
- Protein Modification and Degradation Lab, SKLRD, School of Basic Medical Sciences, Affiliated Cancer Hospital of Guangzhou Medical University, Guangzhou, China
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Rinke J, Chase A, Cross NCP, Hochhaus A, Ernst T. EZH2 in Myeloid Malignancies. Cells 2020; 9:cells9071639. [PMID: 32650416 PMCID: PMC7407223 DOI: 10.3390/cells9071639] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 02/07/2023] Open
Abstract
Our understanding of the significance of epigenetic dysregulation in the pathogenesis of myeloid malignancies has greatly advanced in the past decade. Enhancer of Zeste Homolog 2 (EZH2) is the catalytic core component of the Polycomb Repressive Complex 2 (PRC2), which is responsible for gene silencing through trimethylation of H3K27. EZH2 dysregulation is highly tumorigenic and has been observed in various cancers, with EZH2 acting as an oncogene or a tumor-suppressor depending on cellular context. While loss-of-function mutations of EZH2 frequently affect patients with myelodysplastic/myeloproliferative neoplasms, myelodysplastic syndrome and myelofibrosis, cases of chronic myeloid leukemia (CML) seem to be largely characterized by EZH2 overexpression. A variety of other factors frequently aberrant in myeloid leukemia can affect PRC2 function and disease pathogenesis, including Additional Sex Combs Like 1 (ASXL1) and splicing gene mutations. As the genetic background of myeloid malignancies is largely heterogeneous, it is not surprising that EZH2 mutations act in conjunction with other aberrations. Since EZH2 mutations are considered to be early events in disease pathogenesis, they are of therapeutic interest to researchers, though targeting of EZH2 loss-of-function does present unique challenges. Preliminary research indicates that combined tyrosine kinase inhibitor (TKI) and EZH2 inhibitor therapy may provide a strategy to eliminate the residual disease burden in CML to allow patients to remain in treatment-free remission.
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Affiliation(s)
- Jenny Rinke
- Klinik für Innere Medizin II, Universitätsklinikum Jena, 07743 Jena, Germany; (J.R.); (A.H.)
| | - Andrew Chase
- School of Medicine, University of Southampton, Southampton SO17 1BJ, UK; (A.C.); (N.C.P.C.)
- Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury SP2 8BJ, UK
| | - Nicholas C. P. Cross
- School of Medicine, University of Southampton, Southampton SO17 1BJ, UK; (A.C.); (N.C.P.C.)
- Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury SP2 8BJ, UK
| | - Andreas Hochhaus
- Klinik für Innere Medizin II, Universitätsklinikum Jena, 07743 Jena, Germany; (J.R.); (A.H.)
| | - Thomas Ernst
- Klinik für Innere Medizin II, Universitätsklinikum Jena, 07743 Jena, Germany; (J.R.); (A.H.)
- Correspondence: ; Tel.: +49-3641-9324201; Fax: +49-3641-9324202
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Histone lysine demethylase KDM5B maintains chronic myeloid leukemia via multiple epigenetic actions. Exp Hematol 2020; 82:53-65. [PMID: 32007477 DOI: 10.1016/j.exphem.2020.01.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 01/17/2020] [Accepted: 01/18/2020] [Indexed: 11/23/2022]
Abstract
The histone lysine demethylase KDM5 family is implicated in normal development and stem cell maintenance by epigenetic modulation of histone methylation status. Deregulation of the KDM5 family has been reported in various types of cancers, including hematological malignancies. However, their transcriptional regulatory roles in the context of leukemia remain unclear. Here, we find that KDM5B is strongly expressed in normal CD34+ hematopoietic stem/progenitor cells and chronic myeloid leukemia (CML) cells. Knockdown of KDM5B in K562 CML cells reduced leukemia colony-forming potential. Transcriptome profiling of KDM5B knockdown K562 cells revealed the deregulation of genes involved in myeloid differentiation and Toll-like receptor signaling. Through the integration of transcriptome and ChIP-seq profiling data, we show that KDM5B is enriched at the binding sites of the GATA and AP-1 transcription factor families, suggesting their collaborations in the regulation of transcription. Even though the binding of KDM5B substantially overlapped with H3K4me1 or H3K4me3 mark at gene promoters, only a small subset of the KDM5B targets showed differential expression in association with the histone demethylation activity. By characterizing the interacting proteins in K562 cells, we discovered that KDM5B recruits protein complexes involved in the mRNA processing machinery, implying an alternative epigenetic action mediated by KDM5B in gene regulation. Our study highlights the oncogenic functions of KDM5B in CML cells and suggests that KDM5B is vital to the transcriptional regulation via multiple epigenetic mechanisms.
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10
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Liu X, Cui X, Guan G, Dong Y, Zhang Z. microRNA-192-5p is involved in nerve repair in rats with peripheral nerve injury by regulating XIAP. Cell Cycle 2020; 19:326-338. [PMID: 31944167 DOI: 10.1080/15384101.2019.1710916] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Objective: MicroRNAs (miRNAs) have been demonstrated to engage in the nerve injury, while the effect of microRNA-192-5p (miR-192-5p) on the nerve repair has not yet been well understood. This study is performed to investigate how miR-192-5p affects nerve repair in rats with peripheral nerve injury by regulating X-linked inhibitor of apoptosis protein (XIAP).Methods: The rat model of left sciatic nerve injury was established, and the expression of miR-192-5p was then detected. A series of experiments were conducted to investigate the role of miR-192-5p on nerve repair in rats with peripheral nerve injury. The expression of apoptosis-related proteins (Caspase-3, Bax and Bcl-2) and nerve repair factors (NGF, BDNF, and GAP-43) was measured. Bioinformatics analysis and dual-luciferase reporter gene assay confirmed the targeting relationship between miR-192-5p and XIAP.Results: MiR-192-5p inhibition promoted the recovery of sensory function and the recovery and regeneration in rats with sciatic nerve injury. MiR-192-5p inhibition promoted the recovery of muscle atrophy caused by nerve injury. MiR-192-5p inhibition inhibited neuronal apoptosis by affecting the expression of apoptosis-related proteins and promoted the recovery of nerve function by elevating the expression of nerve repair factors induced by peripheral nerve injury. Bioinformatics analysis and dual-luciferase reporter gene assay confirmed that XIAP was a target gene of miR-192-5p.Conclusion: This study demonstrates that miR-192-5p inhibition can up-regulate the expression of XIAP, decrease the apoptosis of nerve cells, and promote the repair and regeneration of peripheral nerve injury.
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Affiliation(s)
- Xing Liu
- Department of orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Xintao Cui
- Department of orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Guangwei Guan
- Department of orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Ying Dong
- Department of orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Zhenyu Zhang
- Department of orthopedics, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
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11
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Bugler J, Kinstrie R, Scott MT, Vetrie D. Epigenetic Reprogramming and Emerging Epigenetic Therapies in CML. Front Cell Dev Biol 2019; 7:136. [PMID: 31380371 PMCID: PMC6652210 DOI: 10.3389/fcell.2019.00136] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/05/2019] [Indexed: 12/16/2022] Open
Abstract
Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder characterized by BCR-ABL1, an oncogenic fusion gene arising from the Philadelphia chromosome. The development of tyrosine kinase inhibitors (TKIs) to overcome the constitutive tyrosine kinase activity of the BCR-ABL protein has dramatically improved disease management and patient outcomes over the past 20 years. However, the majority of patients are not cured and developing novel therapeutic strategies that target epigenetic processes are a promising avenue to improve cure rates. A number of epigenetic mechanisms are altered or reprogrammed during the development and progression of CML, resulting in alterations in histone modifications, DNA methylation and dysregulation of the transcriptional machinery. In this review these epigenetic alterations are examined and the potential of epigenetic therapies are discussed as a means of eradicating residual disease and offering a potential cure for CML in combination with current therapies.
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Affiliation(s)
| | | | | | - David Vetrie
- Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
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12
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Boddu P, Carter BZ, Verstovsek S, Pemmaraju N. SMACmimetics as potential cancer therapeutics in myeloid malignancies. Br J Haematol 2019; 185:219-231. [DOI: 10.1111/bjh.15829] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Prajwal Boddu
- Department of Hematology and Oncology Yale University School of Medicine New Haven CTUSA
| | - Bing Z. Carter
- Department of Leukemia University of Texas MD Anderson Cancer Center Houston TX USA
| | - Srdan Verstovsek
- Department of Leukemia University of Texas MD Anderson Cancer Center Houston TX USA
| | - Naveen Pemmaraju
- Department of Leukemia University of Texas MD Anderson Cancer Center Houston TX USA
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13
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Sustained NF-κB-STAT3 signaling promotes resistance to Smac mimetics in Glioma stem-like cells but creates a vulnerability to EZH2 inhibition. Cell Death Discov 2019; 5:72. [PMID: 30854231 PMCID: PMC6399311 DOI: 10.1038/s41420-019-0155-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 12/20/2022] Open
Abstract
Glioblastoma is an incurable and highly aggressive brain tumor. Understanding therapeutic resistance and survival mechanisms driving this tumor type is key to finding effective therapies. Smac mimetics (SM) emerged as attractive cancer therapeutics particularly for tumor populations that are highly resistant to conventional apoptosis-inducing therapies. We evaluated the therapeutic efficacy of SM on Glioma stem-like cells (GSCs) and showed that this family of compounds stimulates an adaptive response triggered by TNFα. Increased expression of TNFα results in a prolonged and sustained activation of NF-κB and STAT3 signaling thus activating several tumor cell resistance mechanisms in GSCs. We show that STAT3 activation is contingent on EZH2 activation and uncover a synergistic lethality between SM and EZH2 inhibitors. Therapeutic inhibition of EZH2 impaired the viability of SM-treated GSCs. Our study outlines the molecular underpinnings of SM resistance in glioblastoma and provides mechanistic insight to overcome this resistance and increase therapeutic efficacy.
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14
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Mardani R, Jafari Najaf Abadi MH, Motieian M, Taghizadeh-Boroujeni S, Bayat A, Farsinezhad A, Gheibi Hayat SM, Motieian M, Pourghadamyari H. MicroRNA in leukemia: Tumor suppressors and oncogenes with prognostic potential. J Cell Physiol 2018; 234:8465-8486. [PMID: 30515779 DOI: 10.1002/jcp.27776] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 10/30/2018] [Indexed: 02/06/2023]
Abstract
Leukemia is known as a progressive malignant disease, which destroys the blood-forming organs and results in adverse effects on the proliferation and development of leukocytes and their precursors in the blood and bone marrow. There are four main classes of leukemia including acute leukemia, chronic leukemia, myelogenous leukemia, and lymphocytic leukemia. Given that a variety of internal and external factors could be associated with the initiation and progression of different types of leukemia. One of the important factors is epigenetic regulators such as microRNAs (miRNAs) and long noncoding RNAs (ncRNA). MiRNAs are short ncRNAs which act as tumor suppressor (i.e., miR-15, miR-16, let-7, and miR-127) or oncogene (i.e., miR-155, miR-17-92, miR-21, miR-125b, miR-93, miR-143-p3, miR-196b, and miR-223) in leukemia. It has been shown that deregulation of these molecules are associated with the initiation and progression of leukemia. Hence, miRNAs could be used as potential therapeutic candidates in the treatment of patients with leukemia. Moreover, increasing evidence revealed that miRNAs could be used as diagnostic and prognostic biomarkers in monitoring patients in early stages of disease or after received chemotherapy regimen. It seems that identification and development of new miRNAs could pave to the way to the development new therapeutic platforms for patients with leukemia. Here, we summarized various miRNAs as tumor suppressor and oncogene which could be introduced as therapeutic targets in treatment of leukemia.
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Affiliation(s)
- Rajab Mardani
- Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran
| | | | - Mahsa Motieian
- School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sima Taghizadeh-Boroujeni
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Borujen, Iran
| | - Amir Bayat
- Hematology, Oncology, and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran.,Department of Cell and Molecular Biology, College of Science, Kish International Campus, University of Tehran, Kish, Iran
| | - Alireza Farsinezhad
- Department of Hematology and Medical Laboratory Sciences, Faculty of Allied Medical Sciences, Kerman University of Medical Sciences, Kerman, Iran
| | | | - Mahtab Motieian
- Department of Internal Medicine, Montefiore New Rochelle Hospital, Albert Einstein College of Medicine, New York, New York
| | - Hossein Pourghadamyari
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran.,Department of Clinical Biochemistry, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
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15
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Di Marco M, Ramassone A, Pagotto S, Anastasiadou E, Veronese A, Visone R. MicroRNAs in Autoimmunity and Hematological Malignancies. Int J Mol Sci 2018; 19:ijms19103139. [PMID: 30322050 PMCID: PMC6213554 DOI: 10.3390/ijms19103139] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 10/02/2018] [Indexed: 12/13/2022] Open
Abstract
Autoimmunity and hematological malignancies are often concomitant in patients. A causal bidirectional relationship exists between them. Loss of immunological tolerance with inappropriate activation of the immune system, likely due to environmental and genetic factors, can represent a breeding ground for the appearance of cancer cells and, on the other hand, blood cancers are characterized by imbalanced immune cell subsets that could support the development of the autoimmune clone. Considerable effort has been made for understanding the proteins that have a relevant role in both processes; however, literature advances demonstrate that microRNAs (miRNAs) surface as the epigenetic regulators of those proteins and control networks linked to both autoimmunity and hematological malignancies. Here we review the most up-to-date findings regarding the miRNA-based molecular mechanisms that underpin autoimmunity and hematological malignancies.
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Affiliation(s)
- Mirco Di Marco
- Ageing Research Center and Translational medicine-CeSI-MeT, 66100 Chieti, Italy.
- Department of Medical, Oral and Biotechnological Sciences (DSMOB), "G. d'Annunzio" University Chieti-Pescara, 66100 Chieti, Italy.
| | - Alice Ramassone
- Ageing Research Center and Translational medicine-CeSI-MeT, 66100 Chieti, Italy.
- Department of Medical, Oral and Biotechnological Sciences (DSMOB), "G. d'Annunzio" University Chieti-Pescara, 66100 Chieti, Italy.
| | - Sara Pagotto
- Ageing Research Center and Translational medicine-CeSI-MeT, 66100 Chieti, Italy.
- Department of Medical, Oral and Biotechnological Sciences (DSMOB), "G. d'Annunzio" University Chieti-Pescara, 66100 Chieti, Italy.
| | - Eleni Anastasiadou
- Harvard Medical School Initiative for RNA Medicine, Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| | - Angelo Veronese
- Ageing Research Center and Translational medicine-CeSI-MeT, 66100 Chieti, Italy.
- Department of Medicine and Aging Science (DMSI), "G. d'Annunzio" University Chieti-Pescara, 66100 Chieti, Italy.
| | - Rosa Visone
- Ageing Research Center and Translational medicine-CeSI-MeT, 66100 Chieti, Italy.
- Department of Medical, Oral and Biotechnological Sciences (DSMOB), "G. d'Annunzio" University Chieti-Pescara, 66100 Chieti, Italy.
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16
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Safaei S, Baradaran B, Hagh MF, Alivand MR, Talebi M, Gharibi T, Solali S. Double sword role of EZH2 in leukemia. Biomed Pharmacother 2018; 98:626-635. [DOI: 10.1016/j.biopha.2017.12.059] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/11/2017] [Accepted: 12/14/2017] [Indexed: 12/18/2022] Open
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17
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Zhu X, Chen S, Jiang Y, Xu Y, Zhao Y, Chen L, Li C, Zhou X. Analysis of miRNA expression profiles in melatonin-exposed GC-1 spg cell line. Gene 2018; 642:513-521. [DOI: 10.1016/j.gene.2017.11.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 08/24/2017] [Accepted: 11/28/2017] [Indexed: 12/15/2022]
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18
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Koschmieder S, Vetrie D. Epigenetic dysregulation in chronic myeloid leukaemia: A myriad of mechanisms and therapeutic options. Semin Cancer Biol 2017; 51:180-197. [PMID: 28778403 DOI: 10.1016/j.semcancer.2017.07.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/13/2017] [Accepted: 07/28/2017] [Indexed: 01/08/2023]
Abstract
The onset of global epigenetic changes in chromatin that drive tumor proliferation and heterogeneity is a hallmark of many forms of cancer. Identifying the epigenetic mechanisms that govern these changes and developing therapeutic approaches to modulate them, is a well-established avenue pursued in translational cancer medicine. Chronic myeloid leukemia (CML) arises clonally when a hematopoietic stem cell (HSC) acquires the capacity to produce the constitutively active tyrosine kinase BCR-ABL1 fusion protein which drives tumor development. Treatment with tyrosine kinase inhibitors (TKI) that target BCR-ABL1 has been transformative in CML management but it does not lead to cure in the vast majority of patients. Thus novel therapeutic approaches are required and these must target changes to biological pathways that are aberrant in CML - including those that occur when epigenetic mechanisms are altered. These changes may be due to alterations in DNA or histones, their biochemical modifications and requisite 'writer' proteins, or to dysregulation of various types of non-coding RNAs that collectively function as modulators of transcriptional control and DNA integrity. Here, we review the evidence for subverted epigenetic mechanisms in CML and how these impact on a diverse set of biological pathways, on disease progression, prognosis and drug resistance. We will also discuss recent progress towards developing epigenetic therapies that show promise to improve CML patient care and may lead to improved cure rates.
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Affiliation(s)
- Steffen Koschmieder
- Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
| | - David Vetrie
- Epigenetics Unit, Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom.
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19
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The chronic myeloid leukemia stem cell: stemming the tide of persistence. Blood 2017; 129:1595-1606. [PMID: 28159740 DOI: 10.1182/blood-2016-09-696013] [Citation(s) in RCA: 200] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/04/2016] [Indexed: 12/14/2022] Open
Abstract
Chronic myeloid leukemia (CML) is caused by the acquisition of the tyrosine kinase BCR-ABL1 in a hemopoietic stem cell, transforming it into a leukemic stem cell (LSC) that self-renews, proliferates, and differentiates to give rise to a myeloproliferative disease. Although tyrosine kinase inhibitors (TKIs) that target the kinase activity of BCR-ABL1 have transformed CML from a once-fatal disease to a manageable one for the vast majority of patients, only ∼10% of those who present in chronic phase (CP) can discontinue TKI treatment and maintain a therapy-free remission. Strong evidence now shows that CML LSCs are resistant to the effects of TKIs and persist in all patients on long-term therapy, where they may promote acquired TKI resistance, drive relapse or disease progression, and inevitably represent a bottleneck to cure. Since their discovery in patients almost 2 decades ago, CML LSCs have become a well-recognized exemplar of the cancer stem cell and have been characterized extensively, with the aim of developing new curative therapeutic approaches based on LSC eradication. This review summarizes our current understanding of many of the pathways and mechanisms that promote the survival of the CP CML LSCs and how they can be a source of new gene coding mutations that impact in the clinic. We also review recent preclinical approaches that show promise to eradicate the LSC, and future challenges on the path to cure.
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