351
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Mutations of RNA splicing factors in hematological malignancies. Cancer Lett 2017; 409:1-8. [PMID: 28888996 DOI: 10.1016/j.canlet.2017.08.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/22/2017] [Accepted: 08/28/2017] [Indexed: 01/01/2023]
Abstract
Systematic large-scale cancer genomic studies have produced numerous significant findings. These studies have not only revealed new cancer-promoting genes, but they also have identified cancer-promoting functions of previously known "housekeeping" genes. These studies have identified numerous mutations in genes which play a fundamental role in nuclear precursor mRNA splicing. Somatic mutations and copy number variation in many of the splicing factors which participate in the formation of multiple spliceosomal complexes appear to play a role in many cancers and in particular in myelodysplastic syndromes (MDS). Mutated proteins seem to interfere with the recognition of the authentic splice sites (SS) leading to utilization of suboptimal alternative splicing sites generating aberrantly spliced mRNA isoforms. This short review is focusing on the function of the splice factors involved in the formation of splicing complexes and potential mechanisms which affect usage of the authentic splice site recognition.
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352
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Robertson AG, Shih J, Yau C, Gibb EA, Oba J, Mungall KL, Hess JM, Uzunangelov V, Walter V, Danilova L, Lichtenberg TM, Kucherlapati M, Kimes PK, Tang M, Penson A, Babur O, Akbani R, Bristow CA, Hoadley KA, Iype L, Chang MT, Cherniack AD, Benz C, Mills GB, Verhaak RGW, Griewank KG, Felau I, Zenklusen JC, Gershenwald JE, Schoenfield L, Lazar AJ, Abdel-Rahman MH, Roman-Roman S, Stern MH, Cebulla CM, Williams MD, Jager MJ, Coupland SE, Esmaeli B, Kandoth C, Woodman SE. Integrative Analysis Identifies Four Molecular and Clinical Subsets in Uveal Melanoma. Cancer Cell 2017; 32:204-220.e15. [PMID: 28810145 PMCID: PMC5619925 DOI: 10.1016/j.ccell.2017.07.003] [Citation(s) in RCA: 549] [Impact Index Per Article: 78.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 04/24/2017] [Accepted: 07/09/2017] [Indexed: 12/17/2022]
Abstract
Comprehensive multiplatform analysis of 80 uveal melanomas (UM) identifies four molecularly distinct, clinically relevant subtypes: two associated with poor-prognosis monosomy 3 (M3) and two with better-prognosis disomy 3 (D3). We show that BAP1 loss follows M3 occurrence and correlates with a global DNA methylation state that is distinct from D3-UM. Poor-prognosis M3-UM divide into subsets with divergent genomic aberrations, transcriptional features, and clinical outcomes. We report change-of-function SRSF2 mutations. Within D3-UM, EIF1AX- and SRSF2/SF3B1-mutant tumors have distinct somatic copy number alterations and DNA methylation profiles, providing insight into the biology of these low- versus intermediate-risk clinical mutation subtypes.
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Affiliation(s)
- A Gordon Robertson
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, BC V5Z 4S6, Canada
| | - Juliann Shih
- The Eli and Edythe L. Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA; Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Christina Yau
- Buck Institute for Research on Aging, Novato, CA 94945, USA
| | - Ewan A Gibb
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, BC V5Z 4S6, Canada
| | - Junna Oba
- Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Karen L Mungall
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, BC V5Z 4S6, Canada
| | - Julian M Hess
- The Eli and Edythe L. Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA
| | - Vladislav Uzunangelov
- Department of Biomolecular Engineering, Center for Biomolecular Sciences and Engineering, University of California, Santa Cruz, CA 95064, USA
| | - Vonn Walter
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Public Health Sciences, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Ludmila Danilova
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, MD 21287, USA
| | - Tara M Lichtenberg
- The Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Melanie Kucherlapati
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Patrick K Kimes
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ming Tang
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Alexander Penson
- Human Oncology and Pathogenesis Program, Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA; Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
| | - Ozgun Babur
- Molecular and Medical Genetics, Computational Biology, Oregon Health and Science University, Portland, OR 97239, USA
| | - Rehan Akbani
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Christopher A Bristow
- Institute for Applied Cancer Science, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Katherine A Hoadley
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Lisa Iype
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Matthew T Chang
- Human Oncology and Pathogenesis Program, Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA; Departments of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94122, USA
| | | | - Andrew D Cherniack
- The Eli and Edythe L. Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02142, USA; Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | - Gordon B Mills
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Roel G W Verhaak
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Klaus G Griewank
- Department of Dermatology, University Hospital Essen, 45157 Essen, Germany
| | - Ina Felau
- Center for Cancer Genomics, National Cancer Institute, Bethesda, MD 20892, USA
| | - Jean C Zenklusen
- Center for Cancer Genomics, National Cancer Institute, Bethesda, MD 20892, USA
| | - Jeffrey E Gershenwald
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Lynn Schoenfield
- Department of Pathology, The Ohio State University, Wexner Medical Center, Columbus, OH 43210, USA
| | - Alexander J Lazar
- Department of Pathology, Dermatology and Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mohamed H Abdel-Rahman
- Departments of Ophthalmology and Internal Medicine, Division of Human Genetics, The Ohio State University, Columbus, OH 43210, USA
| | - Sergio Roman-Roman
- Department of Translational Research, Institut Curie, PSL Research University, Paris 75248, France
| | - Marc-Henri Stern
- Department of Translational Research, Institut Curie, PSL Research University, Paris 75248, France
| | - Colleen M Cebulla
- Havener Eye Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43212, USA
| | - Michelle D Williams
- Department of Pathology, Dermatology and Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Martine J Jager
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Sarah E Coupland
- Department of Molecular & Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, Liverpool L7 8TX, UK; Department of Cellular Pathology, Royal Liverpool University Hospital, Liverpool, L69 3GA, UK
| | - Bita Esmaeli
- Orbital Oncology & Ophthalmic Plastic Surgery, Department of Plastic Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Cyriac Kandoth
- Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA.
| | - Scott E Woodman
- Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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353
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Lee SCW, Abdel-Wahab O. Therapeutic targeting of splicing in cancer. Nat Med 2017; 22:976-86. [PMID: 27603132 DOI: 10.1038/nm.4165] [Citation(s) in RCA: 385] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 07/13/2016] [Indexed: 02/07/2023]
Abstract
Recent studies have highlighted that splicing patterns are frequently altered in cancer and that mutations in genes encoding spliceosomal proteins, as well as mutations affecting the splicing of key cancer-associated genes, are enriched in cancer. In parallel, there is also accumulating evidence that several molecular subtypes of cancer are highly dependent on splicing function for cell survival. These findings have resulted in a growing interest in targeting splicing catalysis, splicing regulatory proteins, and/or specific key altered splicing events in the treatment of cancer. Here we present strategies that exist and that are in development to target altered dependency on the spliceosome, as well as aberrant splicing, in cancer. These include drugs to target global splicing in cancer subtypes that are preferentially dependent on wild-type splicing for survival, methods to alter post-translational modifications of splicing-regulating proteins, and strategies to modulate pathologic splicing events and protein-RNA interactions in cancer.
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Affiliation(s)
- Stanley Chun-Wei Lee
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York, USA.,Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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354
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Overexpression of RUNX1 short isoform has an important role in the development of myelodysplastic/myeloproliferative neoplasms. Blood Adv 2017; 1:1382-1386. [PMID: 29296779 DOI: 10.1182/bloodadvances.2016002725] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/23/2017] [Indexed: 12/20/2022] Open
Abstract
RUNX1a, but not RUNX1b, is overexpressed in CD34+ cells from patients with myelodysplastic/myeloproliferative neoplasms.SRSF2P95H mutation induces RUNX1a overexpression and a monocytic phenotype in TF-1 cells.
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355
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Bejar R. Splicing Factor Mutations in Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 907:215-28. [PMID: 27256388 DOI: 10.1007/978-3-319-29073-7_9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Many cancers demonstrate aberrant splicing patterns that contribute to their development and progression. Recently, recurrent somatic mutations of genes encoding core subunits of the spliceosome have been identified in several different cancer types. These mutations are most common in hematologic malignancies like the myelodysplastic syndromes (MDS), acute myeloid leukemia, and chronic lymphocytic leukemia, but also in occur in several solid tumors at lower frequency. The most frequent mutations occur in SF3B1, U2AF1, SRSF2, and ZRSR2 and are largely exclusive of each other. Mutations in SF3B1, U2AF1, and SRSF2 acquire heterozygous missense mutations in specific codons, resembling oncogenes. ZRSR2 mutations include clear loss-of-function variants, a pattern more common to tumor suppressor genes. These splicing factors are associated with distinct clinical phenotypes and patterns of mutation in different malignancies. Mutations have both diagnostic and prognostic relevance. Splicing factor mutations appear to affect only a minority of transcripts which show little overlap by mutation type. How differences in splicing caused by somatic mutations of spliceosome subunits lead to oncogenesis is not clear and may involve different targets in each disease type. However, cells with mutated splicing machinery may be particularly vulnerable to further disruption of the spliceosome suggesting a novel strategy for the targeted therapy of cancers.
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Affiliation(s)
- Rafael Bejar
- Division of Hematology and Oncology, UC San Diego Moores Cancer Center, La Jolla, CA, USA.
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356
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Kim YJ, Abdel-Wahab O. Therapeutic targeting of RNA splicing in myelodysplasia. Semin Hematol 2017; 54:167-173. [PMID: 28958291 DOI: 10.1053/j.seminhematol.2017.06.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 06/22/2017] [Indexed: 01/05/2023]
Abstract
Genomic analysis of patients with myelodysplastic syndromes (MDS) has identified that mutations within genes encoding RNA splicing factors represent the most common class of genetic alterations in MDS. These mutations primarily affect SF3B1, SRSF2, U2AF1, and ZRSR2. Current data suggest that these mutations perturb RNA splicing catalysis in a manner distinct from loss of function but how exactly the global changes in RNA splicing imparted by these mutations result in MDS is not well delineated. At the same time, cells bearing mutations in RNA splicing factors are exquisitely dependent on the presence of the remaining wild-type (WT) allele to maintain residual normal splicing for cell survival. The high frequency of these mutations in MDS, combined with their mutual exclusivity and noteworthy dependence on the WT allele, make targeting RNA splicing attractive in MDS. To this end, two promising therapeutic approaches targeting RNA splicing are being tested clinically currently. These include molecules targeting core RNA splicing catalysis by interfering with the ability of the SF3b complex to interact with RNA, as well as molecules degrading the auxiliary RNA splicing factor RBM39. The preclinical and clinical evaluation of these compounds are discussed here in addition to their potential as therapies for spliceosomal mutant MDS.
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Affiliation(s)
- Young Joon Kim
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY; Leukemia Service, Department\. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY.
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357
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Polycomb repressive complexes in hematological malignancies. Blood 2017; 130:23-29. [DOI: 10.1182/blood-2017-02-739490] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 05/03/2017] [Indexed: 12/21/2022] Open
Abstract
Abstract
The deregulation of polycomb repressive complexes (PRCs) has been reported in a number of hematological malignancies. These complexes exert oncogenic or tumor-suppressive functions depending on tumor type. These findings have revolutionized our understanding of the pathophysiology of hematological malignancies and the impact of deregulated epigenomes in tumor development and progression. The therapeutic targeting of PRCs is currently attracting increasing attention and being extensively examined in clinical studies, leading to new therapeutic strategies that may improve the outcomes of patients with hematological malignancies.
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358
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Abstract
Myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN) are aggressive myeloid malignancies recognized as a distinct category owing to their unique combination of dysplastic and proliferative features. Although current classification schemes still emphasize morphology and exclusionary criteria, disease-defining somatic mutations and/or germline predisposition alleles are increasingly incorporated into diagnostic algorithms. The developing picture suggests that phenotypes are driven mostly by epigenetic mechanisms that reflect a complex interplay between genotype, physiological processes such as ageing and interactions between malignant haematopoietic cells and the stromal microenvironment of the bone marrow. Despite the rapid accumulation of genetic knowledge, therapies have remained nonspecific and largely inefficient. In this Review, we discuss the pathogenesis of MDS/MPN, focusing on the relationship between genotype and phenotype and the molecular underpinnings of epigenetic dysregulation. Starting with the limitations of current therapies, we also explore how the available mechanistic data may be harnessed to inform strategies to develop rational and more effective treatments, and which gaps in our knowledge need to be filled to translate biological understanding into clinical progress.
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Affiliation(s)
- Michael W N Deininger
- Division of Hematology and Hematologic Malignancies, Department of Internal Medicine, University of Utah
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112, USA
| | - Jeffrey W Tyner
- Knight Cancer Institute, Oregon Health and Science University
- Department of Cell, Developmental and Cancer Biology, Oregon Health &Science University, Portland, Oregon 97239, USA
| | - Eric Solary
- INSERM U1170, Gustave Roussy, Faculté de médecine Paris-Sud, Université Paris-Saclay, F-94805 Villejuif, France
- Department of Hematology, Gustave Roussy, F-94805 Villejuif, France
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359
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Malcovati L, Gallì A, Travaglino E, Ambaglio I, Rizzo E, Molteni E, Elena C, Ferretti VV, Catricalà S, Bono E, Todisco G, Bianchessi A, Rumi E, Zibellini S, Pietra D, Boveri E, Camaschella C, Toniolo D, Papaemmanuil E, Ogawa S, Cazzola M. Clinical significance of somatic mutation in unexplained blood cytopenia. Blood 2017; 129:3371-3378. [PMID: 28424163 PMCID: PMC5542849 DOI: 10.1182/blood-2017-01-763425] [Citation(s) in RCA: 331] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/14/2017] [Indexed: 11/20/2022] Open
Abstract
Unexplained blood cytopenias, in particular anemia, are often found in older persons. The relationship between these cytopenias and myeloid neoplasms like myelodysplastic syndromes is currently poorly defined. We studied a prospective cohort of patients with unexplained cytopenia with the aim to estimate the predictive value of somatic mutations for identifying subjects with, or at risk of, developing a myeloid neoplasm. The study included a learning cohort of 683 consecutive patients investigated for unexplained cytopenia, and a validation cohort of 190 patients referred for suspected myeloid neoplasm. Using granulocyte DNA, we looked for somatic mutations in 40 genes that are recurrently mutated in myeloid malignancies. Overall, 435/683 patients carried a somatic mutation in at least 1 of these genes. Carrying a somatic mutation with a variant allele frequency ≥0.10, or carrying 2 or more mutations, had a positive predictive value for diagnosis of myeloid neoplasm equal to 0.86 and 0.88, respectively. Spliceosome gene mutations and comutation patterns involving TET2, DNMT3A, or ASXL1 had positive predictive values for myeloid neoplasm ranging from 0.86 to 1.0. Within subjects with inconclusive diagnostic findings, carrying 1 or more somatic mutations was associated with a high probability of developing a myeloid neoplasm during follow-up (hazard ratio = 13.9, P < .001). The predictive values of mutation analysis were confirmed in the independent validation cohort. The findings of this study indicate that mutation analysis on peripheral blood granulocytes may significantly improve the current diagnostic approach to unexplained cytopenia and more generally the diagnostic accuracy of myeloid neoplasms.
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Affiliation(s)
- Luca Malcovati
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Anna Gallì
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Erica Travaglino
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Ilaria Ambaglio
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | | | | | - Chiara Elena
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | | | - Silvia Catricalà
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Elisa Bono
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Gabriele Todisco
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Antonio Bianchessi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Elisa Rumi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Silvia Zibellini
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Daniela Pietra
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
| | - Emanuela Boveri
- Department of Pathology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Clara Camaschella
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
- Vita Salute University, Milan, Italy
| | - Daniela Toniolo
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | - Elli Papaemmanuil
- Center for Molecular Oncology and Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY; and
| | - Seishi Ogawa
- Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan
| | - Mario Cazzola
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Department of Hematology Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy
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360
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Robust patient-derived xenografts of MDS/MPN overlap syndromes capture the unique characteristics of CMML and JMML. Blood 2017; 130:397-407. [PMID: 28576879 DOI: 10.1182/blood-2017-01-763219] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 06/01/2017] [Indexed: 02/06/2023] Open
Abstract
Chronic myelomonocytic leukemia (CMML) and juvenile myelomonocytic leukemia (JMML) are myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) overlap disorders characterized by monocytosis, myelodysplasia, and a characteristic hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). Currently, there are no available disease-modifying therapies for CMML, nor are there preclinical models that fully recapitulate the unique features of CMML. Through use of immunocompromised mice with transgenic expression of human GM-CSF, interleukin-3, and stem cell factor in a NOD/SCID-IL2Rγnull background (NSGS mice), we demonstrate remarkable engraftment of CMML and JMML providing the first examples of serially transplantable and genetically accurate models of CMML. Xenotransplantation of CD34+ cells (n = 8 patients) or unfractionated bone marrow (BM) or peripheral blood mononuclear cells (n = 10) resulted in robust engraftment of CMML in BM, spleen, liver, and lung of recipients (n = 82 total mice). Engrafted cells were myeloid-restricted and matched the immunophenotype, morphology, and genetic mutations of the corresponding patient. Similar levels of engraftment were seen upon serial transplantation of human CD34+ cells in secondary NSGS recipients (2/5 patients, 6/11 mice), demonstrating the durability of CMML grafts and functionally validating CD34+ cells as harboring the disease-initiating compartment in vivo. Successful engraftments of JMML primary samples were also achieved in all NSGS recipients (n = 4 patients, n = 12 mice). Engraftment of CMML and JMML resulted in overt phenotypic abnormalities and lethality in recipients, which facilitated evaluation of the JAK2/FLT3 inhibitor pacritinib in vivo. These data reveal that NSGS mice support the development of CMML and JMML disease-initiating and mature leukemic cells in vivo, allowing creation of genetically accurate preclinical models of these disorders.
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361
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Abstract
Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic malignancy that may deserve specific management. Defined by a persistent peripheral blood monocytosis ≥1 × 109/L and monocytes accounting for ≥10% of the white blood cells, this aging-associated disease combines cell proliferation as a consequence of myeloid progenitor hypersensitivity to granulocyte-macrophage colony-stimulating factor with myeloid cell dysplasia and ineffective hematopoiesis. The only curative option for CMML remains allogeneic stem cell transplantation. When transplantation is excluded, CMML is stratified into myelodysplastic (white blood cell count <13 × 109/L) and proliferative (white blood cell count ≥13 × 109/L) CMML. In the absence of poor prognostic factors, the management of myelodysplastic CMML is largely inspired from myelodysplastic syndromes, relying on erythropoiesis-stimulating agents to cope with anemia, and careful monitoring and supportive care, whereas the management of proliferative CMML usually relies on cytoreductive agents such as hydroxyurea, although ongoing studies will help delineate the role of hypomethylating agents in this patient population. In the presence of excessive blasts and other poor prognostic factors, hypomethylating agents are the preferred option, even though their impact on leukemic transformation and survival has not been proved. The therapeutic choice is illustrated by 4 clinical situations among the most commonly seen. Although current therapeutic options can improve patient's quality of life, they barely modify disease evolution. Improved understanding of CMML pathophysiology will hopefully lead to the exploration of novel targets that potentially would be curative.
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362
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Jin S, Su H, Tran NT, Song J, Lu SS, Li Y, Huang S, Abdel-Wahab O, Liu Y, Zhao X. Splicing factor SF3B1K700E mutant dysregulates erythroid differentiation via aberrant alternative splicing of transcription factor TAL1. PLoS One 2017; 12:e0175523. [PMID: 28545085 PMCID: PMC5436638 DOI: 10.1371/journal.pone.0175523] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 03/27/2017] [Indexed: 11/18/2022] Open
Abstract
More than 60% of myeloid dysplasia syndrome (MDS) contains mutations in genes encoding for splicing factors such as SF3B1, U2AF, SRSF2 and ZRSR2. Mutations in SF3B1 are associated with 80% cases of refractory anemia with ring sideroblast (RARS), a subtype of MDS. SF3B1K700E is the most frequently mutated site among mutations on SF3B1. Yet the molecular mechanisms on how mutations of splicing factors lead to defective erythropoiesis are not clear. SF3B1K700E mutant binds to an RNA binding protein, RBM15, stronger than the wild type SF3B1 protein in co-immunoprecipitation assays. In addition, K700E mutant alters the RNA splicing of transcription factors TAL1 and GATA1. Via alternative RNA splicing, a novel short TAL1 transcript variant (TAL1s) is generated. Enhanced interaction between SF3B1 and RBM15 promotes the production of full-length TAL1 (TAL1fl) mRNA, while reduction of RBM15 protein level via PRMT1-mediated degradation pathway changes TAL1s/TAL1fl ratio in favor of TAL1s. TAL1s contains the helix-loop-helix DNA binding domain but not the N terminal region upstream of the DNA binding domain. The TAL1s protein loses its interaction with ETO2, which represses early erythropoiesis. In this vein, overexpression of TAL1s stimulates the transcription of β-hemoglobin in human leukemia K562 cells and promotes erythroid differentiation of human cord blood CD34+ cells cultured in erythropoietin-containing medium. Therefore, mutations of SF3B1 may block erythropoiesis via dysregulation of alternative RNA splicing of transcription factor TAL1, and targeting PRMT1 may alleviate the anemic symptoms in MDS patients.
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Affiliation(s)
- Shuiling Jin
- Department of Internal Medicine, Henan Cancer Hospital & Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, China
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Hairui Su
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Ngoc-Tung Tran
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Jing Song
- Department of Internal Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Sydney S. Lu
- Human Oncology & Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Ying Li
- Macau Institute for Applied Research in Medicine and Health, State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau. China
| | - Suming Huang
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Omar Abdel-Wahab
- Human Oncology & Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Yanyan Liu
- Department of Internal Medicine, Henan Cancer Hospital & Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, China
| | - Xinyang Zhao
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, Alabama, United States of America
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363
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Joshi P, Halene S, Abdel-Wahab O. How do messenger RNA splicing alterations drive myelodysplasia? Blood 2017; 129:2465-2470. [PMID: 28348147 PMCID: PMC5418633 DOI: 10.1182/blood-2017-02-692715] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 03/23/2017] [Indexed: 12/21/2022] Open
Abstract
Mutations in RNA splicing factors are the single most common class of genetic alterations in myelodysplastic syndrome (MDS) patients. Although much has been learned about how these mutations affect splicing at a global- and transcript-specific level, critical questions about the role of these mutations in MDS development and maintenance remain. Here we present the questions to be addressed in order to understand the unique enrichment of these mutations in MDS.
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Affiliation(s)
- Poorval Joshi
- Section of Hematology, Yale Comprehensive Cancer Center and Department of Internal Medicine, Yale University School of Medicine, New Haven, CT; and
| | - Stephanie Halene
- Section of Hematology, Yale Comprehensive Cancer Center and Department of Internal Medicine, Yale University School of Medicine, New Haven, CT; and
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program and Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY
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364
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Jenkins JL, Kielkopf CL. Splicing Factor Mutations in Myelodysplasias: Insights from Spliceosome Structures. Trends Genet 2017; 33:336-348. [PMID: 28372848 PMCID: PMC5447463 DOI: 10.1016/j.tig.2017.03.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 02/28/2017] [Accepted: 03/02/2017] [Indexed: 01/08/2023]
Abstract
Somatic mutations of pre-mRNA splicing factors recur among patients with myelodysplastic syndrome (MDS) and related malignancies. Although these MDS-relevant mutations alter the splicing of a subset of transcripts, the mechanisms by which these single amino acid substitutions change gene expression remain controversial. New structures of spliceosome intermediates and associated protein complexes shed light on the molecular interactions mediated by 'hotspots' of the SF3B1 and U2AF1 pre-mRNA splicing factors. The frequently mutated SF3B1 residues contact the pre-mRNA splice site. Based on structural homology with other spliceosome subunits, and recent findings of altered RNA binding by mutant U2AF1 proteins, we suggest that affected U2AF1 residues also contact pre-mRNA. Altered pre-mRNA recognition emerges as a molecular theme among MDS-relevant mutations of pre-mRNA splicing factors.
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Affiliation(s)
- Jermaine L Jenkins
- Center for RNA Biology and Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Clara L Kielkopf
- Center for RNA Biology and Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
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365
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Yip BH, Steeples V, Repapi E, Armstrong RN, Llorian M, Roy S, Shaw J, Dolatshad H, Taylor S, Verma A, Bartenstein M, Vyas P, Cross NC, Malcovati L, Cazzola M, Hellström-Lindberg E, Ogawa S, Smith CW, Pellagatti A, Boultwood J. The U2AF1S34F mutation induces lineage-specific splicing alterations in myelodysplastic syndromes. J Clin Invest 2017; 127:2206-2221. [PMID: 28436936 PMCID: PMC5451246 DOI: 10.1172/jci91363] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 02/21/2017] [Indexed: 12/23/2022] Open
Abstract
Mutations of the splicing factor–encoding gene U2AF1 are frequent in the myelodysplastic syndromes (MDS), a myeloid malignancy, and other cancers. Patients with MDS suffer from peripheral blood cytopenias, including anemia, and an increasing percentage of bone marrow myeloblasts. We studied the impact of the common U2AF1S34F mutation on cellular function and mRNA splicing in the main cell lineages affected in MDS. We demonstrated that U2AF1S34F expression in human hematopoietic progenitors impairs erythroid differentiation and skews granulomonocytic differentiation toward granulocytes. RNA sequencing of erythroid and granulomonocytic colonies revealed that U2AF1S34F induced a higher number of cassette exon splicing events in granulomonocytic cells than in erythroid cells. U2AF1S34F altered mRNA splicing of many transcripts that were expressed in both cell types in a lineage-specific manner. In hematopoietic progenitors, the introduction of isoform changes identified in the U2AF1S34F target genes H2AFY, encoding an H2A histone variant, and STRAP, encoding serine/threonine kinase receptor–associated protein, recapitulated phenotypes associated with U2AF1S34F expression in erythroid and granulomonocytic cells, suggesting a causal link. Furthermore, we showed that isoform modulation of H2AFY and STRAP rescues the erythroid differentiation defect in U2AF1S34F MDS cells, suggesting that splicing modulators could be used therapeutically. These data have critical implications for understanding MDS phenotypic heterogeneity and support the development of therapies targeting splicing abnormalities.
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Affiliation(s)
- Bon Ham Yip
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Violetta Steeples
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Emmanouela Repapi
- The Computational Biology Research Group, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Richard N Armstrong
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Miriam Llorian
- Department of Biochemistry, Downing Site, University of Cambridge, Cambridge, United Kingdom
| | - Swagata Roy
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Jacqueline Shaw
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Hamid Dolatshad
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Stephen Taylor
- The Computational Biology Research Group, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Amit Verma
- Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Paresh Vyas
- Medical Research Council, Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, and Department of Hematology, Oxford University Hospital National Health Service Trust, Oxford, United Kingdom
| | - Nicholas Cp Cross
- Faculty of Medicine, University of Southampton, Southampton, and National Genetics Reference Laboratory (Wessex), Salisbury, United Kingdom
| | - Luca Malcovati
- Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy
| | - Mario Cazzola
- Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy
| | - Eva Hellström-Lindberg
- Center for Hematology and Regenerative Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Seishi Ogawa
- Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan
| | - Christopher Wj Smith
- Department of Biochemistry, Downing Site, University of Cambridge, Cambridge, United Kingdom
| | - Andrea Pellagatti
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
| | - Jacqueline Boultwood
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, and BRC Blood Theme, National Institute for Health Research (NIHR) Oxford Biomedical Centre, Oxford University Hospital, Oxford, United Kingdom
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366
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Kozlovski I, Siegfried Z, Amar-Schwartz A, Karni R. The role of RNA alternative splicing in regulating cancer metabolism. Hum Genet 2017; 136:1113-1127. [PMID: 28429085 DOI: 10.1007/s00439-017-1803-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/13/2017] [Indexed: 12/12/2022]
Abstract
Tumor cells alter their metabolism by a wide array of mechanisms to promote growth and proliferation. Dysregulated expression and/or somatic mutations of key components of the glycolytic pathway/TCA cycle as well as other metabolic pathways allow tumor cells to improve their ability to survive harsh conditions such as hypoxia and the presence of reactive oxygen species, as well as the ability to obtain nutrients to increase lipids, protein, and nucleic acids biogenesis. Approximately 95% of the human protein encoding genes undergo alternative splicing (AS), a regulated process of gene expression that greatly diversifies the proteome by creating multiple proteins from a single gene. In recent years, a growing body of evidence suggests that unbalanced AS, the formation of certain pro-tumorigenic isoforms and the reduction of anti-tumorigenic isoforms, is implicated in a variety of cancers. It is becoming increasingly clear that cancer-associated AS contributes to increased growth and proliferation, partially due to effects on metabolic reprogramming. Here, we summarize the known roles of AS in regulating cancer metabolism. We present evidence supporting the idea that AS, in many types of cancer, acts as a molecular switch that alters metabolism to drive tumorigenesis. We propose that the elucidation of misregulated AS and its downstream effects on cancer metabolism emphasizes the need for new therapeutic approaches aiming to modulate the splicing machinery to selectively target cancer cells.
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Affiliation(s)
- Itamar Kozlovski
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Ein Karem, 91120, Jerusalem, Israel
| | - Zahava Siegfried
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Ein Karem, 91120, Jerusalem, Israel
| | - Adi Amar-Schwartz
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Ein Karem, 91120, Jerusalem, Israel
| | - Rotem Karni
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Ein Karem, 91120, Jerusalem, Israel.
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367
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Goyama S, Kitamura T. Epigenetics in normal and malignant hematopoiesis: An overview and update 2017. Cancer Sci 2017; 108:553-562. [PMID: 28100030 PMCID: PMC5406607 DOI: 10.1111/cas.13168] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/05/2017] [Accepted: 01/11/2017] [Indexed: 12/11/2022] Open
Abstract
Epigenetic regulation in hematopoiesis has been a field of rapid expansion. Genome‐wide analyses have revealed, and will continue to identify genetic alterations in epigenetic genes that are present in various types of hematopoietic neoplasms. Development of new mouse models for individual epigenetic modifiers has revealed their novel, sometimes unexpected, functions. In this review, we provide an overview of genetic alterations within epigenetic genes in various types of hematopoietic neoplasms. We then summarize the physiologic roles of these epigenetic modifiers during hematopoiesis, and describe therapeutic approaches targeting the epigenetic modifications. Interestingly, the mutational spectrum of epigenetic genes indicates that myeloid neoplasms are similar to T‐cell neoplasms, whereas B‐cell lymphomas have distinct features. Furthermore, it appears that the epigenetic mutations related to active transcription are more associated with myeloid/T‐cell neoplasms, whereas those that repress transcription are associated with B‐cell lymphomas. These observations may imply that the global low‐level or high‐level transcriptional activity underlies the development of myeloid/T‐cell tumors or B‐cell tumors, respectively.
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Affiliation(s)
- Susumu Goyama
- Division of Cellular Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Toshio Kitamura
- Division of Cellular Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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368
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Dorn G, Leitner A, Boudet J, Campagne S, von Schroetter C, Moursy A, Aebersold R, Allain FHT. Structural modeling of protein-RNA complexes using crosslinking of segmentally isotope-labeled RNA and MS/MS. Nat Methods 2017; 14:487-490. [PMID: 28346450 PMCID: PMC5505470 DOI: 10.1038/nmeth.4235] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 02/22/2017] [Indexed: 11/09/2022]
Abstract
Ribonucleoproteins (RNPs) are key regulators of cellular function. We established an efficient approach that combines segmental isotope labeling of RNA with photo-crosslinking and tandem mass spectrometry to localize protein-RNA interactions simultaneously at amino acid and nucleotide resolution. The approach was tested on Polypyrimidine Tract Binding Protein 1 and U1 small nuclear RNP and the results support integrative atomic-scale structural modeling thus providing mechanistic insights into RNP regulated processes.
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Affiliation(s)
- G Dorn
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - A Leitner
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - J Boudet
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - S Campagne
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - C von Schroetter
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - A Moursy
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - R Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, 8093 Zürich, Switzerland.,Faculty of Science, University of Zurich, Zürich, Switzerland
| | - F H-T Allain
- Department of Biology, Institute for Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
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369
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Mupo A, Seiler M, Sathiaseelan V, Pance A, Yang Y, Agrawal AA, Iorio F, Bautista R, Pacharne S, Tzelepis K, Manes N, Wright P, Papaemmanuil E, Kent DG, Campbell PC, Buonamici S, Bolli N, Vassiliou GS. Hemopoietic-specific Sf3b1-K700E knock-in mice display the splicing defect seen in human MDS but develop anemia without ring sideroblasts. Leukemia 2017; 31:720-727. [PMID: 27604819 PMCID: PMC5336192 DOI: 10.1038/leu.2016.251] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 08/19/2016] [Indexed: 02/06/2023]
Abstract
Heterozygous somatic mutations affecting the spliceosome gene SF3B1 drive age-related clonal hematopoiesis, myelodysplastic syndromes (MDS) and other neoplasms. To study their role in such disorders, we generated knock-in mice with hematopoietic-specific expression of Sf3b1-K700E, the commonest type of SF3B1 mutation in MDS. Sf3b1K700E/+ animals had impaired erythropoiesis and progressive anemia without ringed sideroblasts, as well as reduced hematopoietic stem cell numbers and host-repopulating fitness. To understand the molecular basis of these observations, we analyzed global RNA splicing in Sf3b1K700E/+ hematopoietic cells. Aberrant splicing was associated with the usage of cryptic 3' splice and branchpoint sites, as described for human SF3B1 mutants. However, we found a little overlap between aberrantly spliced mRNAs in mouse versus human, suggesting that anemia may be a consequence of globally disrupted splicing. Furthermore, the murine orthologues of genes associated with ring sideroblasts in human MDS, including Abcb7 and Tmem14c, were not aberrantly spliced in Sf3b1K700E/+ mice. Our findings demonstrate that, despite significant differences in affected transcripts, there is overlap in the phenotypes associated with SF3B1-K700E between human and mouse. Future studies should focus on understanding the basis of these similarities and differences as a means of deciphering the consequences of spliceosome gene mutations in MDS.
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Affiliation(s)
- A Mupo
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - M Seiler
- H3 Biomedicine, Inc., Cambridge, MA, USA
| | | | - A Pance
- Malaria Programme, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Y Yang
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | | | - F Iorio
- European Bioinformatics, Institute, Hinxton, Cambridge, UK
| | - R Bautista
- LIMS Compute and Infrastructure, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - S Pacharne
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - K Tzelepis
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - N Manes
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - P Wright
- Department of Pathology, Cambridge University Hospitals NHS Trust, Cambridge, UK
| | - E Papaemmanuil
- Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - D G Kent
- Cambridge Stem Cell Institute, Cambridge, UK
| | - P C Campbell
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK
| | | | - N Bolli
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK
- Dipartimento di Oncologia ed Onco-Ematologia, Universita' degli Studi di Milano, Milano, Italy
- Dipartimento di Ematologia ed Onco-Ematologia Pediatrica, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - G S Vassiliou
- Haematological Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Department of Haematology, University of Cambridge, Cambridge, UK
- Department of Haematology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
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370
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Kennedy JA, Ebert BL. Clinical Implications of Genetic Mutations in Myelodysplastic Syndrome. J Clin Oncol 2017; 35:968-974. [PMID: 28297619 DOI: 10.1200/jco.2016.71.0806] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Myelodysplastic syndrome (MDS) is clonal disorder characterized by ineffective hematopoiesis and a tendency to evolve into acute myeloid leukemia (AML). Genetic studies have enabled the identification of a set of recurrently mutated genes central to the pathogenesis of MDS, which can be organized into a limited number of cellular processes, including RNA splicing, epigenetic and traditional transcriptional regulation, and signal transduction. The sequential accumulation of mutations drives disease evolution from asymptomatic clonal hematopoiesis to frank MDS, and, ultimately, to secondary AML. This detailed understanding of the molecular landscape of MDS, coupled with the emergence of cost- and time-effective methodologies for DNA sequencing has led to the introduction of genetic studies into the clinical realm. Here, we review recent advances in our genetic understanding of MDS, with a particular focus on the emerging role for mutational data in clinical management as a potential tool to assist in diagnosis, risk stratification, and therapeutic decision-making.
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Affiliation(s)
- James A Kennedy
- James A. Kennedy, University Health Network, Toronto, Ontario, Canada; James A. Kennedy and Benjamin L. Ebert, Brigham and Women's Hospital; and Benjamin L. Ebert, Dana-Farber Cancer Institute, Boston, MA
| | - Benjamin L Ebert
- James A. Kennedy, University Health Network, Toronto, Ontario, Canada; James A. Kennedy and Benjamin L. Ebert, Brigham and Women's Hospital; and Benjamin L. Ebert, Dana-Farber Cancer Institute, Boston, MA
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371
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Long ZB, Du YL, Han B. [Research progress on clonal acquired sideroblastic anemia]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2017; 38:83-86. [PMID: 28219236 PMCID: PMC7348407 DOI: 10.3760/cma.j.issn.0253-2727.2017.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Indexed: 11/05/2022]
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372
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Luo C, Cheng Y, Liu Y, Chen L, Liu L, Wei N, Xie Z, Wu W, Feng Y. SRSF2 Regulates Alternative Splicing to Drive Hepatocellular Carcinoma Development. Cancer Res 2017; 77:1168-1178. [PMID: 28082404 DOI: 10.1158/0008-5472.can-16-1919] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 12/05/2016] [Accepted: 12/08/2016] [Indexed: 11/16/2022]
Abstract
Aberrant RNA splicing is recognized to contribute to cancer pathogenesis, but the underlying mechanisms remain mainly obscure. Here, we report that the splicing factor SRSF2 is upregulated frequently in human hepatocellular carcinoma (HCC), where this event is associated with poor prognosis in patients. RNA-seq and other molecular analyses were used to identify SRSF2-regulated alternative splicing events. SRSF2 binding within an alternative exon was associated with its inclusion in the RNA, whereas SRSF2 binding in a flanking constitutive exon was associated with exclusion of the alternative exon. Notably, cancer-associated splice variants upregulated by SRSF2 in clinical specimens of HCC were found to be crucial for pathogenesis and progression in hepatoma cells, where SRSF2 expression increased cell proliferation and tumorigenic potential by controlling expression of these variants. Our findings identify SRSF2 as a key regulator of RNA splicing dysregulation in cancer, with possible clinical implications as a candidate prognostic factor in patients with HCC. Cancer Res; 77(5); 1168-78. ©2017 AACR.
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Affiliation(s)
- Chunling Luo
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuanming Cheng
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuguo Liu
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Linlin Chen
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lina Liu
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Ning Wei
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhiqin Xie
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Wenwu Wu
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China. .,The Nurturing Station for the State Key Laboratory of Subtropical Silviculture, Zhejiang Agriculture and Forestry University, Lin'an, China
| | - Ying Feng
- Institute for Nutritional Sciences, Chinese Academy of Sciences, Shanghai, China.
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373
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Mutant U2AF1-expressing cells are sensitive to pharmacological modulation of the spliceosome. Nat Commun 2017; 8:14060. [PMID: 28067246 PMCID: PMC5227701 DOI: 10.1038/ncomms14060] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 11/24/2016] [Indexed: 01/05/2023] Open
Abstract
Somatic mutations in spliceosome genes are detectable in ∼50% of patients with myelodysplastic syndromes (MDS). We hypothesize that cells harbouring spliceosome gene mutations have increased sensitivity to pharmacological perturbation of the spliceosome. We focus on mutant U2AF1 and utilize sudemycin compounds that modulate pre-mRNA splicing. We find that haematopoietic cells expressing mutant U2AF1(S34F), including primary patient cells, have an increased sensitivity to in vitro sudemycin treatment relative to controls. In vivo sudemycin treatment of U2AF1(S34F) transgenic mice alters splicing and reverts haematopoietic progenitor cell expansion induced by mutant U2AF1 expression. The splicing effects of sudemycin and U2AF1(S34F) can be cumulative in cells exposed to both perturbations—drug and mutation—compared with cells exposed to either alone. These cumulative effects may result in downstream phenotypic consequences in sudemycin-treated mutant cells. Taken together, these data suggest a potential for treating haematological cancers harbouring U2AF1 mutations with pre-mRNA splicing modulators like sudemycins. Spliceosome mutations occur in approximately 50% of patients with myelodysplastic syndromes. Here, the authors show that tumour cells harbouring the S34F mutation in the U2AF spliceosome gene is sensitive to compounds that further perturb the spliceosome.
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374
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Sperling AS, Gibson CJ, Ebert BL. The genetics of myelodysplastic syndrome: from clonal haematopoiesis to secondary leukaemia. Nat Rev Cancer 2017; 17:5-19. [PMID: 27834397 PMCID: PMC5470392 DOI: 10.1038/nrc.2016.112] [Citation(s) in RCA: 398] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Myelodysplastic syndrome (MDS) is a clonal disease that arises from the expansion of mutated haematopoietic stem cells. In a spectrum of myeloid disorders ranging from clonal haematopoiesis of indeterminate potential (CHIP) to secondary acute myeloid leukaemia (sAML), MDS is distinguished by the presence of peripheral blood cytopenias, dysplastic haematopoietic differentiation and the absence of features that define acute leukaemia. More than 50 recurrently mutated genes are involved in the pathogenesis of MDS, including genes that encode proteins involved in pre-mRNA splicing, epigenetic regulation and transcription. In this Review we discuss the molecular processes that lead to CHIP and further clonal evolution to MDS and sAML. We also highlight the ways in which these insights are shaping the clinical management of MDS, including classification schemata, prognostic scoring systems and therapeutic approaches.
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Affiliation(s)
- Adam S Sperling
- Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
| | - Christopher J Gibson
- Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
| | - Benjamin L Ebert
- Department of Medical Oncology, Dana-Farber Cancer Institute and Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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375
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Grinfeld J, Nangalia J, Green AR. Molecular determinants of pathogenesis and clinical phenotype in myeloproliferative neoplasms. Haematologica 2017; 102:7-17. [PMID: 27909216 PMCID: PMC5210228 DOI: 10.3324/haematol.2014.113845] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 09/27/2016] [Indexed: 12/22/2022] Open
Abstract
The myeloproliferative neoplasms are a heterogeneous group of clonal disorders characterized by the overproduction of mature cells in the peripheral blood, together with an increased risk of thrombosis and progression to acute myeloid leukemia. The majority of patients with Philadelphia-chromosome negative myeloproliferative neoplasms harbor somatic mutations in Janus kinase 2, leading to constitutive activation. Acquired mutations in calreticulin or myeloproliferative leukemia virus oncogene are found in a significant number of patients with essential thrombocythemia or myelofibrosis, and mutations in numerous epigenetic regulators and spliceosome components are also seen. Although the cellular and molecular consequences of many of these mutations remain unclear, it seems likely that they interact with germline and microenvironmental factors to influence disease pathogenesis. This review will focus on the determinants of specific myeloproliferative neoplasm phenotypes as well as on how an improved understanding of molecular mechanisms can inform our understanding of the disease entities themselves.
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Affiliation(s)
- Jacob Grinfeld
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust/MRC Stem Cell Institute, University of Cambridge, Cambridge, UK
- Department of Haematology, Addenbrooke's Hospital, Cambridge, UK
| | - Jyoti Nangalia
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust/MRC Stem Cell Institute, University of Cambridge, Cambridge, UK
- Department of Haematology, Addenbrooke's Hospital, Cambridge, UK
| | - Anthony R Green
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust/MRC Stem Cell Institute, University of Cambridge, Cambridge, UK
- Department of Haematology, Addenbrooke's Hospital, Cambridge, UK
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376
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Genetic basis and molecular pathophysiology of classical myeloproliferative neoplasms. Blood 2016; 129:667-679. [PMID: 28028029 DOI: 10.1182/blood-2016-10-695940] [Citation(s) in RCA: 402] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 12/06/2016] [Indexed: 02/07/2023] Open
Abstract
The genetic landscape of classical myeloproliferative neoplasm (MPN) is in large part elucidated. The MPN-restricted driver mutations, including those in JAK2, calreticulin (CALR), and myeloproliferative leukemia virus (MPL), abnormally activate the cytokine receptor/JAK2 pathway and their downstream effectors, more particularly the STATs. The most frequent mutation, JAK2V617F, activates the 3 main myeloid cytokine receptors (erythropoietin receptor, granulocyte colony-stimulating factor receptor, and MPL) whereas CALR or MPL mutants are restricted to MPL activation. This explains why JAK2V617F is associated with polycythemia vera, essential thrombocythemia (ET), and primary myelofibrosis (PMF) whereas CALR and MPL mutants are found in ET and PMF. Other mutations in genes involved in epigenetic regulation, splicing, and signaling cooperate with the 3 MPN drivers and play a key role in the PMF pathogenesis. Mutations in epigenetic regulators TET2 and DNMT3A are involved in disease initiation and may precede the acquisition of JAK2V617F. Other mutations in epigenetic regulators such as EZH2 and ASXL1 also play a role in disease initiation and disease progression. Mutations in the splicing machinery are predominantly found in PMF and are implicated in the development of anemia or pancytopenia. Both heterogeneity of classical MPNs and prognosis are determined by a specific genomic landscape, that is, type of MPN driver mutations, association with other mutations, and their order of acquisition. However, factors other than somatic mutations play an important role in disease initiation as well as disease progression such as germ line predisposition, inflammation, and aging. Delineation of these environmental factors will be important to better understand the precise pathogenesis of MPN.
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377
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Abstract
The functional capacity of cells is defined by the transcriptome. Many recent studies have identified variations in the transcriptome of tumors due to alternative splicing changes, as well as mutations in splicing factors and regulatory signals in most tumor types. Some of these alterations have been linked to tumor progression, metastasis, therapy resistance, and other oncogenic processes. Here, we describe the different mechanisms that drive splicing changes in tumors and their impact in cancer. Motivated by the current evidence, we propose a model whereby a subset of the splicing patterns contributes to the definition of specific tumor phenotypes, and may hold potential for the development of novel clinical biomarkers and therapeutic approaches.
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Affiliation(s)
- Babita Singh
- a Pompeu Fabra University, PRBB , Barcelona , Spain
| | - Eduardo Eyras
- a Pompeu Fabra University, PRBB , Barcelona , Spain.,b ICREA , Barcelona , Spain
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378
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Xu F, Liu L, Chang CK, He Q, Wu LY, Zhang Z, Shi WH, Guo J, Zhu Y, Zhao YS, Gu SC, Fei CM, Li X. Genomic loss of EZH2 leads to epigenetic modifications and overexpression of the HOX gene clusters in myelodysplastic syndrome. Oncotarget 2016; 7:8119-30. [PMID: 26812882 PMCID: PMC4884980 DOI: 10.18632/oncotarget.6992] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 01/01/2016] [Indexed: 12/11/2022] Open
Abstract
The role of EZH2 in cancer is complex and may vary depending on cancer type or stage. We examined the effect of altered EZH2 levels on H3K27 methylation, HOX gene expression, and malignant phenotype in myelodysplastic syndrome (MDS) cell lines and an in vivo xenograft model. We also studied links between EZH2 expression and prognosis in MDS patients. Patients with high-grade MDS exhibited lower levels of EZH2 expression than those with low-grade MDS. Low EZH2 expression was associated with high percentages of blasts, shorter survival, and increased transformation of MDS into acute myeloid leukemia (AML). MDS patients frequently had reductions in EZH2 copy number. EZH2 knockdown increased tumor growth capacity and reduced H3K27me3 levels in both MDS-derived leukemia cells and in a xenograft model. H3K27me3 levels were reduced and HOX gene cluster expression was increased in MDS patients. EZH2 knockdown also increased HOX gene cluster expression by reducing H3K27me3, and H3K27 demethylating agents increased HOX gene cluster expression in MDS-derived cell lines. These findings suggest genomic loss of EZH2 contributes to overexpression of the HOX gene clusters in MDS through epigenetic modifications.
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Affiliation(s)
- Feng Xu
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Li Liu
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Chun-Kang Chang
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Qi He
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Ling-Yun Wu
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Zheng Zhang
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Wen-Hui Shi
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Juan Guo
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Yang Zhu
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - You-Shan Zhao
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Shu-Cheng Gu
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Cheng-Ming Fei
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Xiao Li
- Department of Hematology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
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379
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Splicing factor gene mutations in hematologic malignancies. Blood 2016; 129:1260-1269. [PMID: 27940478 DOI: 10.1182/blood-2016-10-692400] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/25/2016] [Indexed: 01/27/2023] Open
Abstract
Alternative splicing generates a diversity of messenger RNA (mRNA) transcripts from a single mRNA precursor and contributes to the complexity of our proteome. Splicing is perturbed by a variety of mechanisms in cancer. Recurrent mutations in splicing factors have emerged as a hallmark of several hematologic malignancies. Splicing factor mutations tend to occur in the founding clone of myeloid cancers, and these mutations have recently been identified in blood cells from normal, healthy elderly individuals with clonal hematopoiesis who are at increased risk of subsequently developing a hematopoietic malignancy, suggesting that these mutations contribute to disease initiation. Splicing factor mutations change the pattern of splicing in primary patient and mouse hematopoietic cells and alter hematopoietic differentiation and maturation in animal models. Recent developments in this field are reviewed here, with an emphasis on the clinical consequences of splicing factor mutations, mechanistic insights from animal models, and implications for development of novel therapies targeting the precursor mRNA splicing pathway.
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380
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Wang L, Brooks AN, Fan J, Wan Y, Gambe R, Li S, Hergert S, Yin S, Freeman SS, Levin JZ, Fan L, Seiler M, Buonamici S, Smith PG, Chau KF, Cibulskis CL, Zhang W, Rassenti LZ, Ghia EM, Kipps TJ, Fernandes S, Bloch DB, Kotliar D, Landau DA, Shukla SA, Aster JC, Reed R, DeLuca DS, Brown JR, Neuberg D, Getz G, Livak KJ, Meyerson MM, Kharchenko PV, Wu CJ. Transcriptomic Characterization of SF3B1 Mutation Reveals Its Pleiotropic Effects in Chronic Lymphocytic Leukemia. Cancer Cell 2016; 30:750-763. [PMID: 27818134 PMCID: PMC5127278 DOI: 10.1016/j.ccell.2016.10.005] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 09/01/2016] [Accepted: 10/04/2016] [Indexed: 12/16/2022]
Abstract
Mutations in SF3B1, which encodes a spliceosome component, are associated with poor outcome in chronic lymphocytic leukemia (CLL), but how these contribute to CLL progression remains poorly understood. We undertook a transcriptomic characterization of primary human CLL cells to identify transcripts and pathways affected by SF3B1 mutation. Splicing alterations, identified in the analysis of bulk cells, were confirmed in single SF3B1-mutated CLL cells and also found in cell lines ectopically expressing mutant SF3B1. SF3B1 mutation was found to dysregulate multiple cellular functions including DNA damage response, telomere maintenance, and Notch signaling (mediated through KLF8 upregulation, increased TERC and TERT expression, or altered splicing of DVL2 transcript, respectively). SF3B1 mutation leads to diverse changes in CLL-related pathways.
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Affiliation(s)
- Lili Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Angela N Brooks
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA; University of California, Santa Cruz, CA 95064, USA
| | - Jean Fan
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Youzhong Wan
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; National Engineering Laboratory of AIDS Vaccine, School of Life Science, Jilin University, Changchun, Jilin, PRC
| | - Rutendo Gambe
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Shuqiang Li
- Fluidigm Corporation, South San Francisco, CA 94080, USA
| | - Sarah Hergert
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Shanye Yin
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | | | - Joshua Z Levin
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - Lin Fan
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | | | | | | | | | | | - Wandi Zhang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Laura Z Rassenti
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emanuela M Ghia
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Thomas J Kipps
- Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stacey Fernandes
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Donald B Bloch
- Center for Immunology and Inflammatory Disease, Massachusetts General Hospital, Boston, MA 02115, USA
| | | | - Dan A Landau
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Sachet A Shukla
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Robin Reed
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - David S DeLuca
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | - Jennifer R Brown
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Donna Neuberg
- Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Gad Getz
- Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA
| | | | - Matthew M Meyerson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Catherine J Wu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Dana 540, 44 Binney Street, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA; Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA.
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381
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Yoshimi A, Abdel-Wahab O. Molecular Pathways: Understanding and Targeting Mutant Spliceosomal Proteins. Clin Cancer Res 2016; 23:336-341. [PMID: 27836865 DOI: 10.1158/1078-0432.ccr-16-0131] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/09/2016] [Accepted: 10/11/2016] [Indexed: 02/06/2023]
Abstract
Splicing of precursor messenger RNA is a critical step in regulating gene expression, and major advances are being made in understanding the composition and structure of the enzymatic complex that performs splicing, which is termed the "spliceosome." In parallel, there has been increased appreciation for diverse mechanisms by which alterations in splicing contribute to cancer pathogenesis. Key among these include change-of-function mutations in genes encoding spliceosomal proteins. Such mutations are among the most common genetic alterations in myeloid and lymphoid leukemias, making efforts to therapeutically target cells bearing these mutations critical. To this end, recent studies have clarified that pharmacologic modulation of splicing may be preferentially lethal for cells bearing spliceosomal mutations and may also have a role in the therapy of MYC-driven cancers. This has culminated in the initiation of a clinical trial of a novel oral spliceosome modulatory compound targeting the SF3B complex, and several novel alternative approaches to target splicing are in development as reviewed here. There is now, therefore, a great need to understand the mechanistic basis of altered spliceosomal function in cancers and to study the effects of spliceosomal modulatory compounds in preclinical settings and in well-designed clinical trials. Clin Cancer Res; 23(2); 336-41. ©2016 AACR.
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Affiliation(s)
- Akihide Yoshimi
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, New York
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, New York.
- Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
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382
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Abstract
Cancer results from multistep pathogenesis, yet the pre-malignant states that precede the development of many hematologic malignancies have been difficult to identify. Recent genomic studies of blood DNA from tens of thousands of people have revealed the presence of remarkably common, age-associated somatic mutations in genes associated with hematologic malignancies. These somatic mutations drive the expansion from a single founding cell to a detectable hematopoietic clone. Owing to the admixed nature of blood that provides a sampling of blood cell production throughout the body, clonal hematopoiesis is a rare view into the biology of pre-malignancy and the direct effects of pre-cancerous lesions on organ dysfunction. Indeed, clonal hematopoiesis is associated not only with increased risk of hematologic malignancy, but also with cardiovascular disease and overall mortality. Here we review rapid advances in the genetic understanding of clonal hematopoiesis and nascent evidence implicating clonal hematopoiesis in malignant and non-malignant age-related disease.
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Affiliation(s)
- Max Jan
- Department of Pathology, Massachusetts General Hospital, Boston, MA
| | - Benjamin L Ebert
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Broad Institute of MIT and Harvard, Cambridge, MA.
| | - Siddhartha Jaiswal
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
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383
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The NLRP3 inflammasome functions as a driver of the myelodysplastic syndrome phenotype. Blood 2016; 128:2960-2975. [PMID: 27737891 DOI: 10.1182/blood-2016-07-730556] [Citation(s) in RCA: 255] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/03/2016] [Indexed: 02/07/2023] Open
Abstract
Despite genetic heterogeneity, myelodysplastic syndromes (MDSs) share features of cytological dysplasia and ineffective hematopoiesis. We report that a hallmark of MDSs is activation of the NLRP3 inflammasome, which drives clonal expansion and pyroptotic cell death. Independent of genotype, MDS hematopoietic stem and progenitor cells (HSPCs) overexpress inflammasome proteins and manifest activated NLRP3 complexes that direct activation of caspase-1, generation of interleukin-1β (IL-1β) and IL-18, and pyroptotic cell death. Mechanistically, pyroptosis is triggered by the alarmin S100A9 that is found in excess in MDS HSPCs and bone marrow plasma. Further, like somatic gene mutations, S100A9-induced signaling activates NADPH oxidase (NOX), increasing levels of reactive oxygen species (ROS) that initiate cation influx, cell swelling, and β-catenin activation. Notably, knockdown of NLRP3 or caspase-1, neutralization of S100A9, and pharmacologic inhibition of NLRP3 or NOX suppress pyroptosis, ROS generation, and nuclear β-catenin in MDSs and are sufficient to restore effective hematopoiesis. Thus, alarmins and founder gene mutations in MDSs license a common redox-sensitive inflammasome circuit, which suggests new avenues for therapeutic intervention.
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384
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Wassef M, Margueron R. The Multiple Facets of PRC2 Alterations in Cancers. J Mol Biol 2016; 429:1978-1993. [PMID: 27742591 DOI: 10.1016/j.jmb.2016.10.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 12/12/2022]
Abstract
Genome sequencing of large cohorts of tumors has revealed that mutations in genes encoding chromatin regulators are frequent in cancer. However, the precise contribution of these mutations to tumor development often remains elusive. Here, we review the current knowledge concerning the alterations of the Polycomb machinery in cancer, with a particular focus on the Polycomb repressive complex 2 (PRC2), a key chromatin modifier involved in the maintenance of transcriptional silencing. A broad variety of alterations can impair PRC2 activity; yet, overall, only one type of alteration is found in a given class of tumor. We discuss the potential impact of the various types of PRC2 alterations on gene expression. We propose that the distinct set of genes regulated by PRC2, depending on tumor etiology, constrain the type of alteration of PRC2 that can fuel tumor development. Beyond this specificity, we propose that PRC2 and, more generally, chromatin regulators act as gatekeepers of transcriptional integrity, a role that often confers a tumor-suppressive function.
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Affiliation(s)
- M Wassef
- Institut Curie, PSL Research University, - 26, rue d'Ulm, 75005 Paris, France; INSERM U934, CNRS UMR3215, Paris, France, 75005
| | - R Margueron
- Institut Curie, PSL Research University, - 26, rue d'Ulm, 75005 Paris, France; INSERM U934, CNRS UMR3215, Paris, France, 75005.
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385
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Impact of combinatorial dysfunctions of Tet2 and Ezh2 on the epigenome in the pathogenesis of myelodysplastic syndrome. Leukemia 2016; 31:861-871. [DOI: 10.1038/leu.2016.268] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 08/31/2016] [Accepted: 09/06/2016] [Indexed: 12/11/2022]
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386
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Qiu J, Zhou B, Thol F, Zhou Y, Chen L, Shao C, DeBoever C, Hou J, Li H, Chaturvedi A, Ganser A, Bejar R, Zhang DE, Fu XD, Heuser M. Distinct splicing signatures affect converged pathways in myelodysplastic syndrome patients carrying mutations in different splicing regulators. RNA (NEW YORK, N.Y.) 2016; 22:1535-1549. [PMID: 27492256 PMCID: PMC5029452 DOI: 10.1261/rna.056101.116] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 06/08/2016] [Indexed: 06/06/2023]
Abstract
Myelodysplastic syndromes (MDS) are heterogeneous myeloid disorders with prevalent mutations in several splicing factors, but the splicing programs linked to specific mutations or MDS in general remain to be systematically defined. We applied RASL-seq, a sensitive and cost-effective platform, to interrogate 5502 annotated splicing events in 169 samples from MDS patients or healthy individuals. We found that splicing signatures associated with normal hematopoietic lineages are largely related to cell signaling and differentiation programs, whereas MDS-linked signatures are primarily involved in cell cycle control and DNA damage responses. Despite the shared roles of affected splicing factors in the 3' splice site definition, mutations in U2AF1, SRSF2, and SF3B1 affect divergent splicing programs, and interestingly, the affected genes fall into converging cancer-related pathways. A risk score derived from 11 splicing events appears to be independently associated with an MDS prognosis and AML transformation, suggesting potential clinical relevance of altered splicing patterns in MDS.
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Affiliation(s)
- Jinsong Qiu
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Bing Zhou
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Felicitas Thol
- Department of Hematology, Hemostasis, Oncology and Stem cell Transplantation, Hannover Medical School, 30625 Hannover, Germany
| | - Yu Zhou
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Liang Chen
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Changwei Shao
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Christopher DeBoever
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Jiayi Hou
- Clinical and Translational Research Institute, University of California, San Diego, La Jolla, California 92093, USA
| | - Hairi Li
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Anuhar Chaturvedi
- Department of Hematology, Hemostasis, Oncology and Stem cell Transplantation, Hannover Medical School, 30625 Hannover, Germany
| | - Arnold Ganser
- Department of Hematology, Hemostasis, Oncology and Stem cell Transplantation, Hannover Medical School, 30625 Hannover, Germany
| | - Rafael Bejar
- Division of Hematology-Oncology, Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Dong-Er Zhang
- Department of Pathology, Moores Cancer Center, University of California, San Diego, La Jolla, California 92093, USA
| | - Xiang-Dong Fu
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, USA Institute for Genomic Medicine, University of California, San Diego, La Jolla, California 92093, USA
| | - Michael Heuser
- Department of Hematology, Hemostasis, Oncology and Stem cell Transplantation, Hannover Medical School, 30625 Hannover, Germany
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387
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Obeng EA, Chappell RJ, Seiler M, Chen MC, Campagna DR, Schmidt PJ, Schneider RK, Lord AM, Wang L, Gambe RG, McConkey ME, Ali AM, Raza A, Yu L, Buonamici S, Smith PG, Mullally A, Wu CJ, Fleming MD, Ebert BL. Physiologic Expression of Sf3b1(K700E) Causes Impaired Erythropoiesis, Aberrant Splicing, and Sensitivity to Therapeutic Spliceosome Modulation. Cancer Cell 2016; 30:404-417. [PMID: 27622333 PMCID: PMC5023069 DOI: 10.1016/j.ccell.2016.08.006] [Citation(s) in RCA: 280] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 04/29/2016] [Accepted: 08/16/2016] [Indexed: 12/20/2022]
Abstract
More than 80% of patients with the refractory anemia with ring sideroblasts subtype of myelodysplastic syndrome (MDS) have mutations in Splicing Factor 3B, Subunit 1 (SF3B1). We generated a conditional knockin mouse model of the most common SF3B1 mutation, Sf3b1(K700E). Sf3b1(K700E) mice develop macrocytic anemia due to a terminal erythroid maturation defect, erythroid dysplasia, and long-term hematopoietic stem cell (LT-HSC) expansion. Sf3b1(K700E) myeloid progenitors and SF3B1-mutant MDS patient samples demonstrate aberrant 3' splice-site selection associated with increased nonsense-mediated decay. Tet2 loss cooperates with Sf3b1(K700E) to cause a more severe erythroid and LT-HSC phenotype. Furthermore, the spliceosome modulator, E7017, selectively kills SF3B1(K700E)-expressing cells. Thus, SF3B1(K700E) expression reflects the phenotype of the mutation in MDS and may be a therapeutic target in MDS.
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Affiliation(s)
- Esther A Obeng
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA; Division of Hematology/Oncology, Department of Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Ryan J Chappell
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Michelle C Chen
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Dean R Campagna
- Department of Pathology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Paul J Schmidt
- Department of Pathology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Rebekka K Schneider
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Allegra M Lord
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lili Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Rutendo G Gambe
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Marie E McConkey
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Abdullah M Ali
- Division of Hematology/Oncology, Columbia University Medical Center, New York, NY 10027, USA
| | - Azra Raza
- Division of Hematology/Oncology, Columbia University Medical Center, New York, NY 10027, USA
| | - Lihua Yu
- H3 Biomedicine, Inc., Cambridge, MA 03129, USA
| | | | | | - Ann Mullally
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Catherine J Wu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Mark D Fleming
- Department of Pathology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Benjamin L Ebert
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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388
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Abstract
In this issue of Cancer Cell, Obeng et al. identify the consequences of expressing the most common mutation in the spliceosomal gene SF3B1 on hematopoiesis. The knockin mouse model described represents a valuable tool to dissect the effects of SF3B1 mutations on transformation, splicing, and less well-characterized functions of SF3B1.
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Affiliation(s)
- Daichi Inoue
- Human Oncology and Pathogenesis Program, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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389
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Abstract
Tumor-associated alterations in RNA splicing result either from mutations in splicing-regulatory elements or changes in components of the splicing machinery. This review summarizes our current understanding of the role of splicing-factor alterations in human cancers. We describe splicing-factor alterations detected in human tumors and the resulting changes in splicing, highlighting cell-type-specific similarities and differences. We review the mechanisms of splicing-factor regulation in normal and cancer cells. Finally, we summarize recent efforts to develop novel cancer therapies, based on targeting either the oncogenic splicing events or their upstream splicing regulators.
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Affiliation(s)
- Olga Anczuków
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | - Adrian R Krainer
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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390
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Ntziachristos P, Abdel-Wahab O, Aifantis I. Emerging concepts of epigenetic dysregulation in hematological malignancies. Nat Immunol 2016; 17:1016-24. [PMID: 27478938 PMCID: PMC5134743 DOI: 10.1038/ni.3517] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/21/2016] [Indexed: 12/12/2022]
Abstract
The past decade brought a revolution in understanding of the structure, topology and disease-inducing lesions of RNA and DNA, fueled by unprecedented progress in next-generation sequencing. This technological revolution has also affected understanding of the epigenome and has provided unique opportunities for the analysis of DNA and histone modifications, as well as the first map of the non-protein-coding genome and three-dimensional (3D) chromosomal interactions. Overall, these advances have facilitated studies that combine genetic, transcriptomics and epigenomics data to address a wide range of issues ranging from understanding the role of the epigenome in development to targeting the transcription of noncoding genes in human cancer. Here we describe recent insights into epigenetic dysregulation characteristic of the malignant differentiation of blood stem cells based on studies of alterations that affect epigenetic complexes, enhancers, chromatin, long noncoding RNAs (lncRNAs), RNA splicing, nuclear topology and the 3D conformation of chromatin.
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Affiliation(s)
- Panagiotis Ntziachristos
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Iannis Aifantis
- Department of Pathology and Perlmutter Cancer Center, New York University School of Medicine, New York, New York, USA
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391
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Suzuki Y, Tomita A, Nakamura F, Iriyama C, Shirahata-Adachi M, Shimada K, Akashi A, Ishikawa Y, Kaneda N, Kiyoi H. Peripheral blood cell-free DNA is an alternative tumor DNA source reflecting disease status in myelodysplastic syndromes. Cancer Sci 2016; 107:1329-37. [PMID: 27323954 PMCID: PMC5021037 DOI: 10.1111/cas.12994] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/13/2016] [Accepted: 06/17/2016] [Indexed: 12/17/2022] Open
Abstract
Genetic alterations in myelodysplastic syndromes (MDS) are critical for pathogenesis. We previously showed that peripheral blood cell-free DNA (PBcfDNA) may be more sensitive for genetic/epigenetic analyses than whole bone marrow (BM) cells and mononuclear cells in peripheral blood (PB). Here we analyzed the detailed features of PBcfDNA and its utility in genetic analyses in MDS. The plasma-PBcfDNA concentration in MDS and related diseases (N = 33) was significantly higher than that in healthy donors (N = 14; P = 0.041) and in International Prognostic Scoring System higher-risk groups than that in lower-risk groups (P = 0.034). The concentration of plasma-/serum-PBcfDNA was significantly correlated with the serum lactate dehydrogenase level (both P < 0.0001) and the blast cell count in PB (P = 0.034 and 0.025, respectively). One nanogram of PBcfDNA was sufficient for one assay of Sanger sequencing using optimized primer sets to amplify approximately 160-bp PCR products. PBcfDNA (approximately 50 ng) can also be utilized for targeted sequencing. Almost all mutations detected in BM-DNA were also detected using corresponding PBcfDNA. Analyses using serially harvested PBcfDNA from an RAEB-2 patient showed that the somatic mutations and a single nucleotide polymorphism that were detected before allogeneic transplantation were undetectable after transplantation, indicating that PBcfDNA likely comes from MDS clones that reflect the disease status. PBcfDNA may be a safer and easier alternative to obtain tumor DNA in MDS.
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Affiliation(s)
- Yasuhiro Suzuki
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akihiro Tomita
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
| | - Fumika Nakamura
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Department of Analytical Neurobiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Chisako Iriyama
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Mizuho Shirahata-Adachi
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kazuyuki Shimada
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Institute for Adavanced Research, Nagoya University, Nagoya, Japan
| | - Akimi Akashi
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuichi Ishikawa
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Norio Kaneda
- Department of Analytical Neurobiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Hitoshi Kiyoi
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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392
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Skrdlant L, Stark JM, Lin RJ. Myelodysplasia-associated mutations in serine/arginine-rich splicing factor SRSF2 lead to alternative splicing of CDC25C. BMC Mol Biol 2016; 17:18. [PMID: 27552991 PMCID: PMC4994158 DOI: 10.1186/s12867-016-0071-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 08/16/2016] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Serine-arginine rich splicing factor 2 (SRSF2) is a protein known for its role in RNA splicing and genome stability. It has been recently discovered that SRSF2, along with other splicing regulators, is frequently mutated in patients with myelodysplastic syndrome (MDS). The most common MDS mutations in SRSF2 occur at proline 95; the mutant proteins are shown to have different RNA binding preferences, which may contribute to splicing changes detected in mutant cells. However, the influence of these SRSF2 MDS-associated mutations on specific splicing events remains poorly understood. RESULTS A tetracycline-inducible TF-1 erythroleukemia cell line was transduced with retroviruses to create cell lines expressing HA-tagged wildtype SRSF2, SRSF2 with proline 95 point mutations found in MDS, or SRSF2 with a deletion of one of the four major domains of the protein. Effects of these mutants on apoptosis and specific alternative splicing events were evaluated. Cells were also treated with DNA damaging drugs for comparison. MDS-related P95 point mutants of SRSF2 were expressed and phosphorylated at similar levels as wildtype SRSF2. However, cells expressing mutant SRSF2 exhibited higher levels of apoptosis than cells expressing wildtype SRSF2. Regarding alternative splicing events, in nearly all examined cases, SRSF2 P95 mutants acted in a similar fashion as the wildtype SRSF2. However, cells expressing SRSF2 P95 mutants had a percent increase in the C5 spliced isoform of cell division cycle 25C (CDC25C). The same alternative splicing of CDC25C was detected by treating cells with DNA damaging drugs, such as cisplatin, camptothecin, and trichostatin A at appropriate dosage. However, unlike DNA damaging drugs, SRSF2 P95 mutants did not activate the Ataxia telangiectasia mutated (ATM) pathway. CONCLUSION SRSF2 P95 mutants lead to alternative splicing of CDC25C in a manner that is not dependent on the DNA damage response.
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Affiliation(s)
- Lindsey Skrdlant
- Department of Molecular and Cellular Biology, Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010 USA
| | - Jeremy M. Stark
- Department of Cancer Genetics and Epigenetics, Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010 USA
| | - Ren-Jang Lin
- Department of Molecular and Cellular Biology, Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010 USA
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393
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Pellagatti A, Boultwood J. Splicing factor gene mutations in the myelodysplastic syndromes: impact on disease phenotype and therapeutic applications. Adv Biol Regul 2016; 63:59-70. [PMID: 27639445 DOI: 10.1016/j.jbior.2016.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 08/18/2016] [Accepted: 08/18/2016] [Indexed: 01/05/2023]
Abstract
Splicing factor gene mutations are the most frequent mutations found in patients with the myeloid malignancy myelodysplastic syndrome (MDS), suggesting that spliceosomal dysfunction plays a major role in disease pathogenesis. The aberrantly spliced target genes and deregulated cellular pathways associated with the commonly mutated splicing factor genes in MDS (SF3B1, SRSF2 and U2AF1) are being identified, illuminating the molecular mechanisms underlying MDS. Emerging data from mouse modeling studies indicate that the presence of splicing factor gene mutations can lead to bone marrow hematopoietic stem/myeloid progenitor cell expansion, impaired hematopoiesis and dysplastic differentiation that are hallmarks of MDS. Importantly, recent evidence suggests that spliceosome inhibitors and splicing modulators may have therapeutic value in the treatment of splicing factor mutant myeloid malignancies.
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Affiliation(s)
- Andrea Pellagatti
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford; NIHR Biomedical Research Centre, Oxford, UK.
| | - Jacqueline Boultwood
- Bloodwise Molecular Haematology Unit, Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford; NIHR Biomedical Research Centre, Oxford, UK.
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394
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Zeidan AM, Stahl M, Komrokji R. Emerging biological therapies for the treatment of myelodysplastic syndromes. Expert Opin Emerg Drugs 2016; 21:283-300. [DOI: 10.1080/14728214.2016.1220534] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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395
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Cancer-associated SF3B1 mutants recognize otherwise inaccessible cryptic 3' splice sites within RNA secondary structures. Oncogene 2016; 36:1123-1133. [PMID: 27524419 PMCID: PMC5311031 DOI: 10.1038/onc.2016.279] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 06/14/2016] [Accepted: 07/01/2016] [Indexed: 02/08/2023]
Abstract
Recurrent mutations in core splicing factors have been reported in several clonal disorders, including cancers. Mutations in SF3B1, a component of the U2 splicing complex, are the most common. SF3B1 mutations are associated with aberrant pre-mRNA splicing using cryptic 3’ splice sites (3’SS) but the mechanism of their selection is not clear. To understand how cryptic 3’SS are selected, we performed comprehensive analysis of transcriptome-wide changes to splicing and gene expression associated with SF3B1 mutations in patient samples as well as an experimental model of inducible expression. Hundreds of cryptic 3’SS were detectable across the genome in cells expressing mutant SF3B1. These 3’SS are typically sequestered within RNA secondary structures and poorly accessible compared to their corresponding canonical 3’SS. We hypothesized that these cryptic 3’SS are inaccessible during normal splicing catalysis and that this constraint is overcome in spliceosomes containing mutant SF3B1. This model of secondary structure-dependent selection of cryptic 3’SS was found across multiple clonal processes associated with SF3B1 mutations (myelodysplastic syndrome and chronic lymphocytic leukemia). We validated our model predictions in mini-gene splicing assays. Additionally, we found deregulated expression of proteins with relevant functions in splicing factor-related diseases both in association with aberrant splicing and without corresponding splicing changes. Our results show that SF3B1 mutations are associated with a distinct splicing program shared across multiple clonal processes and define a biochemical mechanism for altered 3’SS choice.
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396
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Yang J, Yao DM, Ma JC, Yang L, Guo H, Wen XM, Xiao GF, Qian Z, Lin J, Qian J. The prognostic implication of SRSF2 mutations in Chinese patients with acute myeloid leukemia. Tumour Biol 2016; 37:10107-14. [PMID: 26820131 DOI: 10.1007/s13277-015-4716-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/21/2015] [Indexed: 12/21/2022] Open
Abstract
Recently, somatic mutations in SRSF2 gene have been discovered in a proportion of hematologic malignancies including acute myeloid leukemia (AML). This study was aimed to investigate SRSF2 mutations in Chinese AML patients. High-resolution melting analysis (HRMA) was developed to screen SRSF2 mutations in 249 cases with AML, and then direct DNA sequencing was used to verify the results of HRMA. In this study, 3.6 % (9/249) of Chinese AML patients were found with heterozygous SRSF2 mutations. Patients with SRSF2 mutations were older than those with wild-type SRSF2 (P = 0.014). No differences in the sex, blood parameters, French-American-British classification (FAB) subtypes, and karyotypes were observed between AML patients with and without SRSF2 mutations. Although the overall survival (OS) of SRSF2-mutated patients was inferior to those without mutations in both whole AML patients (median 4 vs. 11 months, respectively; P = 0.006) and cytogenetically normal patients (median 2 vs. 12 months, respectively; P = 0.008), multiple analysis disclosed that SRSF2 mutation was not an independent prognostic factor in AML patients. These results suggest that SRSF2 mutation occurs at a low frequency in aged AML patients and might not be associated with adverse prognosis in Chinese AML patients.
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Affiliation(s)
- Jing Yang
- Department of Hematology, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Dong-Ming Yao
- Department of Laboratory Medicine, Affiliated People's Hospital of Jiangsu University, Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Ji-Chun Ma
- Laboratory Center, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Lei Yang
- Department of Hematology, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Hong Guo
- Laboratory Center, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Xiang-Mei Wen
- Laboratory Center, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Gao-Fei Xiao
- Laboratory Center, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Zhen Qian
- Department of Hematology, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China
| | - Jiang Lin
- Laboratory Center, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China.
| | - Jun Qian
- Department of Hematology, Affiliated People's Hospital of Jiangsu University, 8 Dianli Rd., Zhenjiang, Jiangsu, 212002, People's Republic of China.
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397
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Furukawa Y, Kikuchi J. Epigenetic mechanisms of cell adhesion-mediated drug resistance in multiple myeloma. Int J Hematol 2016; 104:281-92. [DOI: 10.1007/s12185-016-2048-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 06/17/2016] [Indexed: 12/13/2022]
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398
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The genomic landscape of myeloid neoplasms with myelodysplasia and its clinical implications. Curr Opin Oncol 2016; 27:551-9. [PMID: 26352542 DOI: 10.1097/cco.0000000000000229] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
PURPOSE OF REVIEW This article will review the most recent advances in the understanding of the genetic basis of myeloid neoplasms with myelodysplasia and will discuss its clinical implications. RECENT FINDINGS Recurrent somatic mutations have been identified in about 90% of patients with myeloid neoplasms with myelodysplasia, involving genes of RNA splicing, DNA methylation, histone modification, transcription regulation, DNA repair, signal transduction, and cohesin complex. Somatic mutations are acquired in a linear manner in a multipotent hematopoietic stem cell, resulting in a growth advantage at the stem cell level and in defective differentiation and maturation of hematopoietic precursors. Recently, evidence has been provided of age-related hematopoietic clones, driven by mutations of genes recurrently mutated in myeloid neoplasms. These hematopoietic clones may represent either premalignant clones with the potential to progress to myeloid neoplasm or small malignant clones at a preclinical stage. SUMMARY The available evidence clearly indicates that greater understanding of the molecular basis of myeloid neoplasms with myelodysplasia has relevant implications in the classification of these disorders, as well as in predicting disease risk and response to specific treatment modalities, and may open avenues of research leading to novel therapeutic options and personalized treatment in the individual patient.
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399
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Abstract
The recent genomic characterization of cancers has revealed recurrent somatic point mutations and copy number changes affecting genes encoding RNA splicing factors. Initial studies of these 'spliceosomal mutations' suggest that the proteins bearing these mutations exhibit altered splice site and/or exon recognition preferences relative to their wild-type counterparts, resulting in cancer-specific mis-splicing. Such changes in the splicing machinery may create novel vulnerabilities in cancer cells that can be therapeutically exploited using compounds that can influence the splicing process. Further studies to dissect the biochemical, genomic and biological effects of spliceosomal mutations are crucial for the development of cancer therapies targeted at these mutations.
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Affiliation(s)
- Heidi Dvinge
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Eunhee Kim
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Leukemia Service, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Robert K. Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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400
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Mughal TI, Abdel-Wahab O, Rampal R, Mesa R, Koschmieder S, Levine R, Hehlmann R, Saglio G, Barbui T, Van Etten RA. Contemporary insights into the pathogenesis and treatment of chronic myeloproliferative neoplasms. Leuk Lymphoma 2016; 57:1517-26. [PMID: 27240645 PMCID: PMC6077976 DOI: 10.1080/10428194.2016.1185783] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This review is based on the deliberations at the 5th John Goldman Colloquium held in Estoril on 2nd October 2015 and the 9th post-ASH International Workshop on chronic myeloid leukemia (CML) and BCR-ABL1-negative myeloproliferative neoplasms (MPN) which took place on the 10th-11th December 2014, immediately following the 56th American Society of Hematology Annual Meeting. It has been updated since and summarizes the most recent advances in the biology and therapy of these diseases, in particular updates of genetics of MPN, novel insights from mouse MPN models, targeting CML stem cells and its niche; clinical advances include updates on JAK2 inhibitors and other therapeutic approaches to BCR-ABL1-negative MPNs, the use of alpha interferons, updates on tyrosine kinase inhibitors (TKI) randomized trials in CML, TKI cessation studies, and optimal monitoring strategies.
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MESH Headings
- Animals
- Antineoplastic Agents/administration & dosage
- Antineoplastic Agents/adverse effects
- Antineoplastic Agents/therapeutic use
- Antineoplastic Combined Chemotherapy Protocols/adverse effects
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Disease Models, Animal
- Genetic Predisposition to Disease
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Mice
- Molecular Targeted Therapy
- Mutation
- Myeloproliferative Disorders/diagnosis
- Myeloproliferative Disorders/etiology
- Myeloproliferative Disorders/mortality
- Myeloproliferative Disorders/therapy
- Protein Kinase Inhibitors/administration & dosage
- Protein Kinase Inhibitors/adverse effects
- Protein Kinase Inhibitors/therapeutic use
- Risk Assessment
- Treatment Outcome
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Affiliation(s)
| | | | - Raajit Rampal
- b Memorial Sloan Kettering Cancer Center , New York , NY , USA
| | - Ruben Mesa
- c Mayo Clinic Cancer Center , Scottsdale , AZ , USA
| | - Steffen Koschmieder
- d Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine , RWTH Aachen University , Aachen , Germany
| | - Ross Levine
- b Memorial Sloan Kettering Cancer Center , New York , NY , USA
| | | | | | - Tiziano Barbui
- g Papa Giovani XXIII Hospital and Research Center , Bergamo , Italy
| | - Richard A Van Etten
- h Chao Family Comprehensive Cancer Center, University of California Irvine , Irvine , CA , USA
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