151
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Adusumalli S, Ngian Z, Lin W, Benoukraf T, Ong C. Increased intron retention is a post-transcriptional signature associated with progressive aging and Alzheimer's disease. Aging Cell 2019; 18:e12928. [PMID: 30868713 PMCID: PMC6516162 DOI: 10.1111/acel.12928] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 12/18/2018] [Indexed: 12/23/2022] Open
Abstract
Intron retention (IR) by alternative splicing is a conserved regulatory mechanism that can affect gene expression and protein function during adult development and age-onset diseases. However, it remains unclear whether IR undergoes spatial or temporal changes during different stages of aging or neurodegeneration like Alzheimer's disease (AD). By profiling the transcriptome of Drosophila head cells at different ages, we observed a significant increase in IR events for many genes during aging. Differential IR affects distinct biological functions at different ages and occurs at several AD-associated genes in older adults. The increased nucleosome occupancy at the differentially retained introns in young animals suggests that it may regulate the level of IR during aging. Notably, an increase in the number of IR events was also observed in healthy older mouse and human brain tissues, as well as in the cerebellum and frontal cortex from independent AD cohorts. Genes with differential IR shared many common features, including shorter intron length, no perturbation in their mRNA level, and enrichment for biological functions that are associated with mRNA processing and proteostasis. The differentially retained introns identified in AD frontal cortex have higher GC content, with many of their mRNA transcripts showing an altered level of protein expression compared to control samples. Taken together, our results suggest that an increased IR is an conserved signature that is associated with aging. By affecting pathways involved in mRNA and protein homeostasis, changes of IR pattern during aging may regulate the transition from healthy to pathological state in late-onset sporadic AD.
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Affiliation(s)
- Swarnaseetha Adusumalli
- Temasek Life Sciences Laboratory National University of Singapore Singapore
- Department of Biological Sciences National University of Singapore Singapore
| | - Zhen‐Kai Ngian
- Temasek Life Sciences Laboratory National University of Singapore Singapore
| | - Wei‐Qi Lin
- Temasek Life Sciences Laboratory National University of Singapore Singapore
| | - Touati Benoukraf
- Cancer Science Institute of Singapore National University of Singapore Singapore
- Discipline of Genetics, Faculty of Medicine Memorial University of Newfoundland St. John’s Newfoundland and Labrador Canada
| | - Chin‐Tong Ong
- Temasek Life Sciences Laboratory National University of Singapore Singapore
- Department of Biological Sciences National University of Singapore Singapore
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152
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Zuckerman B, Ulitsky I. Predictive models of subcellular localization of long RNAs. RNA (NEW YORK, N.Y.) 2019; 25:557-572. [PMID: 30745363 PMCID: PMC6467007 DOI: 10.1261/rna.068288.118] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 02/07/2019] [Indexed: 05/14/2023]
Abstract
Export to the cytoplasm is a key regulatory junction for both protein-coding mRNAs and long noncoding RNAs (lncRNAs), and cytoplasmic enrichment varies dramatically both within and between those groups. We used a new computational approach and RNA-seq data from human and mouse cells to quantify the genome-wide association between cytoplasmic/nuclear ratios of both gene groups and various factors, including expression levels, splicing efficiency, gene architecture, chromatin marks, and sequence elements. Splicing efficiency emerged as the main predictive factor, explaining up to a third of the variability in localization. Combination with other features allowed predictive models that could explain up to 45% of the variance for protein-coding genes and up to 34% for lncRNAs. Factors associated with localization were similar between lncRNAs and mRNAs with some important differences. Readily accessible features can thus be used to predict RNA localization.
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Affiliation(s)
- Binyamin Zuckerman
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Igor Ulitsky
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
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153
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Bhuvaneshwar K, Harris M, Gusev Y, Madhavan S, Iyer R, Vilboux T, Deeken J, Yang E, Shankar S. Genome sequencing analysis of blood cells identifies germline haplotypes strongly associated with drug resistance in osteosarcoma patients. BMC Cancer 2019; 19:357. [PMID: 30991985 PMCID: PMC6466653 DOI: 10.1186/s12885-019-5474-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 03/14/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Osteosarcoma is the most common malignant bone tumor in children. Survival remains poor among histologically poor responders, and there is a need to identify them at diagnosis to avoid delivering ineffective therapy. Genetic variation contributes to a wide range of response and toxicity related to chemotherapy. The aim of this study is to use sequencing of blood cells to identify germline haplotypes strongly associated with drug resistance in osteosarcoma patients. METHODS We used sequencing data from two patient datasets, from Inova Hospital and the NCI TARGET. We explored the effect of mutation hotspots, in the form of haplotypes, associated with relapse outcome. We then mapped the single nucleotide polymorphisms (SNPs) in these haplotypes to genes and pathways. We also performed a targeted analysis of mutations in Drug Metabolizing Enzymes and Transporter (DMET) genes associated with tumor necrosis and survival. RESULTS We found intronic and intergenic hotspot regions from 26 genes common to both the TARGET and INOVA datasets significantly associated with relapse outcome. Among significant results were mutations in genes belonging to AKR enzyme family, cell-cell adhesion biological process and the PI3K pathways; as well as variants in SLC22 family associated with both tumor necrosis and overall survival. The SNPs from our results were confirmed using Sanger sequencing. Our results included known as well as novel SNPs and haplotypes in genes associated with drug resistance. CONCLUSION We show that combining next generation sequencing data from multiple datasets and defined clinical data can better identify relevant pathway associations and clinically actionable variants, as well as provide insights into drug response mechanisms.
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Affiliation(s)
- Krithika Bhuvaneshwar
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington DC, USA
| | - Michael Harris
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington DC, USA
| | - Yuriy Gusev
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington DC, USA
| | - Subha Madhavan
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington DC, USA
| | | | | | - John Deeken
- Inova Translational Medicine Institute, Fairfax, VA USA
| | - Elizabeth Yang
- Inova Children’s Hospital, Falls Church, VA USA
- Center for Cancer and Blood Disorders of Northern Virginia, Pediatric Specialists of Virginia, Falls Church, VA USA
- George Washington University School of Medicine, Washington DC, USA
- Virginia Commonwealth University School of Medicine, Inova Campus, Falls Church, VA USA
| | - Sadhna Shankar
- Inova Children’s Hospital, Falls Church, VA USA
- Center for Cancer and Blood Disorders of Northern Virginia, Pediatric Specialists of Virginia, Falls Church, VA USA
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154
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Du Y, Li S, Du R, Shi N, Arai S, Chen S, Wang A, Zhang Y, Fang Z, Zhang T, Ma W. Modularized Perturbation of Alternative Splicing Across Human Cancers. Front Genet 2019; 10:246. [PMID: 31024612 PMCID: PMC6463002 DOI: 10.3389/fgene.2019.00246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 03/05/2019] [Indexed: 01/06/2023] Open
Abstract
Splicing perturbation in cancers contribute to different aspects of cancer cell progression. However, the complete functional impact of cancer-associated splicing have not been fully characterized. Comprehensive large-scale studies are essential to unravel the dominant patterns of cancer-associated splicing. Here we analyzed the genome-wide splicing data in 16 cancer types with normal samples, identified differential splicing events in each cancer type. Then we took a network-based and modularized approach to reconstruct cancer-associated splicing networks, determine the module structures, and evaluate their prognosis relevance. This approach in total identified 51 splicing modules, among which 10/51 modules are related to patient survival, 8/51 are related to progression-free interval, and 5/51 are significant in both. Most of the 51 modules show significant enrichment of important biological functions, such as stem cell proliferation, cell cycle, cell growth, DNA repair, receptor or kinase signaling, and VEGF vessel development. Module-based clustering grouped cancer types according to their tissue-of-origins, consistent with previous pan-cancer studies based on integrative clustering. Interestingly, 13/51 modules are highly common across different cancer types, suggesting the existence of pan-cancer splicing perturbations. Together, modularized perturbation of splicing represents an functionally important and common mechanism across cancer types.
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Affiliation(s)
- Yabing Du
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Shoumiao Li
- Department of Surgery, Anyang Tumor Hospital, Anyang, China
| | - Ranran Du
- Institute of Medical Information, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Ni Shi
- Comprehensive Cancer Center, Ohio State University, Columbus, OH, United States
| | - Seiji Arai
- Department of Hematology and Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
- Department of Urology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Sai Chen
- Department of Clinical Medicine, Xinxiang Medical University, Xinxiang, China
| | - Aijie Wang
- Department of Clinical Medicine, Xinxiang Medical University, Xinxiang, China
| | - Yu Zhang
- Bioinformatics Group, Medcurius Co., Zhejiang, China
| | - Zhaoyuan Fang
- Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai, China
| | - Tengfei Zhang
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Medical College, Henan Polytechnic University, Jiaozuo, China
| | - Wang Ma
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Medical College, Henan Polytechnic University, Jiaozuo, China
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155
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Carazo F, Campuzano L, Cendoya X, Planes FJ, Rubio A. TranscriptAchilles: a genome-wide platform to predict isoform biomarkers of gene essentiality in cancer. Gigascience 2019; 8:giz021. [PMID: 30942869 PMCID: PMC6446222 DOI: 10.1093/gigascience/giz021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/18/2018] [Accepted: 02/07/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Aberrant alternative splicing plays a key role in cancer development. In recent years, alternative splicing has been used as a prognosis biomarker, a therapy response biomarker, and even as a therapeutic target. Next-generation RNA sequencing has an unprecedented potential to measure the transcriptome. However, due to the complexity of dealing with isoforms, the scientific community has not sufficiently exploited this valuable resource in precision medicine. FINDINGS We present TranscriptAchilles, the first large-scale tool to predict transcript biomarkers associated with gene essentiality in cancer. This application integrates 412 loss-of-function RNA interference screens of >17,000 genes, together with their corresponding whole-transcriptome expression profiling. Using this tool, we have studied which are the cancer subtypes for which alternative splicing plays a significant role to state gene essentiality. In addition, we include a case study of renal cell carcinoma that shows the biological soundness of the results. The databases, the source code, and a guide to build the platform within a Docker container are available at GitLab. The application is also available online. CONCLUSIONS TranscriptAchilles provides a user-friendly web interface to identify transcript or gene biomarkers of gene essentiality, which could be used as a starting point for a drug development project. This approach opens a wide range of translational applications in cancer.
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Affiliation(s)
- Fernando Carazo
- Tecnun (University of Navarra), Paseo Manuel Lardizábal 15, 20018 San Sebastián, Spain. Department of Biomedical Engineering and Sciences
| | - Lucía Campuzano
- University of Luxembourg, 2, avenue de l'Université, 4365 Esch-sur-Alzette, Luxembourg
| | - Xabier Cendoya
- Tecnun (University of Navarra), Paseo Manuel Lardizábal 15, 20018 San Sebastián, Spain. Department of Biomedical Engineering and Sciences
| | - Francisco J Planes
- Tecnun (University of Navarra), Paseo Manuel Lardizábal 15, 20018 San Sebastián, Spain. Department of Biomedical Engineering and Sciences
| | - Angel Rubio
- Tecnun (University of Navarra), Paseo Manuel Lardizábal 15, 20018 San Sebastián, Spain. Department of Biomedical Engineering and Sciences
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156
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Gene-Specific Intron Retention Serves as Molecular Signature that Distinguishes Melanoma from Non-Melanoma Cancer Cells in Greek Patients. Int J Mol Sci 2019; 20:ijms20040937. [PMID: 30795533 PMCID: PMC6412294 DOI: 10.3390/ijms20040937] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/15/2019] [Accepted: 02/20/2019] [Indexed: 12/19/2022] Open
Abstract
Background: Skin cancer represents the most common human malignancy, and it includes BCC, SCC, and melanoma. Since melanoma is one of the most aggressive types of cancer, we have herein attempted to develop a gene-specific intron retention signature that can distinguish BCC and SCC from melanoma biopsy tumors. Methods: Intron retention events were examined through RT-sqPCR protocols, using total RNA preparations derived from BCC, SCC, and melanoma Greek biopsy specimens. Intron-hosted miRNA species and their target transcripts were predicted via the miRbase and miRDB bioinformatics platforms, respectively. Ιntronic ORFs were recognized through the ORF Finder application. Generation and visualization of protein interactomes were achieved by the IntAct and Cytoscape softwares, while tertiary protein structures were produced by using the I-TASSER online server. Results: c-MYC and Sestrin-1 genes proved to undergo intron retention specifically in melanoma. Interaction maps of proteins encoded by genes being potentially targeted by retained intron-accommodated miRNAs were generated and SRPX2 was additionally delivered to our melanoma-specific signature. Novel ORFs were identified in MCT4 and Sestrin-1 introns, with potentially critical roles in melanoma development. Conclusions: The property of c-MYC, Sestrin-1, and SRPX2 genes to retain specific introns could be clinically used to molecularly differentiate non-melanoma from melanoma tumors.
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157
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Frankiw L, Majumdar D, Burns C, Vlach L, Moradian A, Sweredoski MJ, Baltimore D. BUD13 Promotes a Type I Interferon Response by Countering Intron Retention in Irf7. Mol Cell 2019; 73:803-814.e6. [DOI: 10.1016/j.molcel.2018.11.038] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 10/20/2018] [Accepted: 11/29/2018] [Indexed: 01/12/2023]
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158
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Li Y, Yu S, Wang X, Ye X, He B, Quan M, Gao Y. SRPK1 facilitates tumor cell growth via modulating the small nucleolar RNA expression in gastric cancer. J Cell Physiol 2019; 234:13582-13591. [PMID: 30633341 DOI: 10.1002/jcp.28036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 11/30/2018] [Indexed: 01/11/2023]
Abstract
Serine-arginine protein kinase 1 (SRPK1) is the main regulator in alternative splicing by phosphorylating splicing factors rich in serine/arginine repeats. Its overexpression has been found in multiple cancer types and contributes to cancer development. Here we report the role of SRPK1 and underlying mechanism in gastric cancer (GC) cell growth. We found that SRPK1 was frequently upregulated in GC samples compared with their adjacent corresponding normal tissues by immunohistochemistry and western blot analysis. Knockdown of SRPK1 in GC cells suppressed cell growth in cell viability assays, colony formation assays and nude mice xenograft model, whereas overexpression of SRPK1 promotes opposite phenotypes in these assays. By a complementary DNA microarray analysis, we found that SRPK1 knockdown had significant inhibitory effects on a majority of small nucleolar RNAs expression. Among them, snoRA42, snoRA74A, and snoRD10 were selected for further functional experiments. Cell growth curves on a plate and in soft agar indicated that the three snoRNAs play potential oncogenic function in GC. In addition, SRPK1 could co-immunoprecipitated with NCL, a nucleolar phosphoprotein involved in the synthesis and maturation of ribosomes. These results suggested that SRPK1 contributes to GC development by a new possible mechanism involving snoRNAs mediated signaling.
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Affiliation(s)
- Yandong Li
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.,Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shijun Yu
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xiao Wang
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xiaojuan Ye
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.,Department of Hematology & Oncology, the People's Hospital of Beilun District, Beilun Branch Hospital of the First Affiliated Hospital of Medical School of Zhejiang University, Ningbo, China
| | - Bin He
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Ming Quan
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yong Gao
- Department of Oncology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
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159
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D'Agostino VG, Sighel D, Zucal C, Bonomo I, Micaelli M, Lolli G, Provenzani A, Quattrone A, Adami V. Screening Approaches for Targeting Ribonucleoprotein Complexes: A New Dimension for Drug Discovery. SLAS DISCOVERY 2019; 24:314-331. [PMID: 30616427 DOI: 10.1177/2472555218818065] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
RNA-binding proteins (RBPs) are pleiotropic factors that control the processing and functional compartmentalization of transcripts by binding primarily to mRNA untranslated regions (UTRs). The competitive and/or cooperative interplay between RBPs and an array of coding and noncoding RNAs (ncRNAs) determines the posttranscriptional control of gene expression, influencing protein production. Recently, a variety of well-recognized and noncanonical RBP domains have been revealed by modern system-wide analyses, underlying an evolving classification of ribonucleoproteins (RNPs) and their importance in governing physiological RNA metabolism. The possibility of targeting selected RNA-protein interactions with small molecules is now expanding the concept of protein "druggability," with new implications for medicinal chemistry and for a deeper characterization of the mechanism of action of bioactive compounds. Here, taking SF3B1, HuR, LIN28, and Musashi proteins as paradigmatic case studies, we review the strategies applied for targeting RBPs, with emphasis on the technological advancements to study protein-RNA interactions and on the requirements of appropriate validation strategies to parallel high-throughput screening (HTS) efforts.
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Affiliation(s)
- Vito Giuseppe D'Agostino
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Denise Sighel
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Chiara Zucal
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Isabelle Bonomo
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Mariachiara Micaelli
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Graziano Lolli
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Alessandro Provenzani
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Alessandro Quattrone
- 1 University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Valentina Adami
- 2 University of Trento, HTS Core Facility, Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
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160
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Olender J, Lee NH. Role of Alternative Splicing in Prostate Cancer Aggressiveness and Drug Resistance in African Americans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1164:119-139. [PMID: 31576545 PMCID: PMC6777849 DOI: 10.1007/978-3-030-22254-3_10] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Alternative splicing, the process of removing introns and joining exons of pre-mRNA, is critical for growth, development, tissue homeostasis, and species diversity. Dysregulation of alternative splicing can initiate and drive disease. Aberrant alternative splicing has been shown to promote the "hallmarks of cancer" in both hematological and solid cancers. Of interest, recent work has focused on the role of alternative splicing in prostate cancer and prostate cancer health disparities. We will provide a review of prostate cancer health disparities involving the African American population, alternative RNA splicing, and alternative splicing in prostate cancer. Lastly, we will summarize our work on differential alternative splicing in prostate cancer disparities and its implications for disparate health outcomes and therapeutic targets.
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Affiliation(s)
- Jacqueline Olender
- Department of Pharmacology and Physiology, GW Cancer Center, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Norman H Lee
- Department of Pharmacology and Physiology, GW Cancer Center, George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
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161
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Gurova KV. Chromatin Stability as a Target for Cancer Treatment. Bioessays 2019; 41:e1800141. [PMID: 30566250 PMCID: PMC6522245 DOI: 10.1002/bies.201800141] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/29/2018] [Indexed: 12/14/2022]
Abstract
In this essay, I propose that DNA-binding anti-cancer drugs work more via chromatin disruption than DNA damage. Success of long-awaited drugs targeting cancer-specific drivers is limited by the heterogeneity of tumors. Therefore, chemotherapy acting via universal targets (e.g., DNA) is still the mainstream treatment for cancer. Nevertheless, the problem with targeting DNA is insufficient efficacy due to high toxicity. I propose that this problem stems from the presumption that DNA damage is critical for the anti-cancer activity of these drugs. DNA in cells exists as chromatin, and many DNA-targeting drugs alter chromatin structure by destabilizing nucleosomes and inducing histone eviction from chromatin. This effect has been largely ignored because DNA damage is seen as the major reason for anti-cancer activity. I discuss how DNA-binding molecules destabilize chromatin, why this effect is more toxic to tumoral than normal cells, and why cells die as a result of chromatin destabilization.
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Affiliation(s)
- Katerina V Gurova
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Elm and Carlton Streets, Buffalo, NY, 14263. Tel 1-716-845-4760,
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162
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Pai AA, Luca F. Environmental influences on RNA processing: Biochemical, molecular and genetic regulators of cellular response. WILEY INTERDISCIPLINARY REVIEWS. RNA 2019; 10:e1503. [PMID: 30216698 PMCID: PMC6294667 DOI: 10.1002/wrna.1503] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/19/2018] [Accepted: 08/01/2018] [Indexed: 12/16/2022]
Abstract
RNA processing has emerged as a key mechanistic step in the regulation of the cellular response to environmental perturbation. Recent work has uncovered extensive remodeling of transcriptome composition upon environmental perturbation and linked the impacts of this molecular plasticity to health and disease outcomes. These isoform changes and their underlying mechanisms are varied-involving alternative sites of transcription initiation, alternative splicing, and alternative cleavage at the 3' end of the mRNA. The mechanisms and consequences of differential RNA processing have been characterized across a range of common environmental insults, including chemical stimuli, immune stimuli, heat stress, and cancer pathogenesis. In each case, there are perturbation-specific contributions of local (cis) regulatory elements or global (trans) factors and downstream consequences. Overall, it is clear that choices in isoform usage involve a balance between the usage of specific genetic elements (i.e., splice sites, polyadenylation sites) and the timing at which certain decisions are made (i.e., transcription elongation rate). Fine-tuned cellular responses to environmental perturbation are often dependent on the genetic makeup of the cell. Genetic analyses of interindividual variation in splicing have identified genetic effects on splicing that contribute to variation in complex traits. Finally, the increase in the number of tissue types and environmental conditions analyzed for RNA processing is paralleled by the need to develop appropriate analytical tools. The combination of large datasets, novel methods and conditions explored promises to provide a much greater understanding of the role of RNA processing response in human phenotypic variation. This article is categorized under: RNA Processing > RNA Editing and Modification RNA Evolution and Genomics > Computational Analyses of RNA RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Athma A Pai
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Francesca Luca
- Center for Molecular Medicine and Genetics, and Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan
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163
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Anufrieva KS, Shender VO, Arapidi GP, Lagarkova MA, Govorun VM. The Diverse Roles of Spliceosomal Proteins in the Regulation of Cell Processes. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2019. [DOI: 10.1134/s1068162019010035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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164
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Rani AQM, Farea M, Maeta K, Kawaguchi T, Awano H, Nagai M, Nishio H, Matsuo M. Identification of the shortest splice variant of Dp71, together with five known variants, in glioblastoma cells. Biochem Biophys Res Commun 2019; 508:640-645. [DOI: 10.1016/j.bbrc.2018.11.168] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 11/27/2018] [Indexed: 12/11/2022]
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165
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Smart AC, Margolis CA, Pimentel H, He MX, Miao D, Adeegbe D, Fugmann T, Wong KK, Van Allen EM. Intron retention is a source of neoepitopes in cancer. Nat Biotechnol 2018; 36:1056-1058. [PMID: 30114007 PMCID: PMC6226333 DOI: 10.1038/nbt.4239] [Citation(s) in RCA: 178] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 08/06/2018] [Indexed: 12/30/2022]
Abstract
We present an in silico approach to identifying neoepitopes derived from intron retention events in tumor transcriptomes. Using mass spectrometry immunopeptidome analysis, we show that retained intron neoepitopes are processed and presented on MHC I on the surface of cancer cell lines. RNA-derived neoepitopes should be considered for prospective personalized cancer vaccine development.
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Affiliation(s)
- Alicia C. Smart
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02179, USA
| | - Claire A. Margolis
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02179, USA
| | - Harold Pimentel
- Department of Genetics and Biology, Stanford University, Stanford, CA 94305, USA
| | - Meng Xiao He
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02179, USA
| | - Diana Miao
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02179, USA
| | - Dennis Adeegbe
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Perlmutter Cancer Center at NYU Langone Medical Center, New York, NY 10016, USA
| | | | - Kwok-Kin Wong
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Perlmutter Cancer Center at NYU Langone Medical Center, New York, NY 10016, USA
| | - Eliezer M. Van Allen
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02179, USA
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166
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Zhao L, Yi S. Transcriptional landscape of alternative splicing during peripheral nerve injury. J Cell Physiol 2018; 234:6876-6885. [PMID: 30362529 DOI: 10.1002/jcp.27446] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/27/2018] [Indexed: 12/27/2022]
Abstract
Alternative splicing (AS) regulates a variety of biological activities in numerous tissues and organs, including the nervous system. However, the existence and specific roles of AS events during peripheral nerve repair and regeneration remain largely undetermined. In the current study, by mapping splice-crossing sequence reads, we identified AS events and relevant spliced genes in rat sciatic nerve stumps following sciatic nerve crush. AS-related genes at 1, 4, 7, and 14 days post nerve crush were compared with those at 0 day to discover alternatively spliced genes induced by sciatic nerve crush. These injury-induced alternatively spliced genes were then categorized to diseases and biological functions, genetic networks, and canonical signaling pathways. Bioinformatic analysis indicated that these alternatively spliced genes were mainly correlated to immune response, cellular growth, and cellular function maintenance. Our study elucidated AS events following peripheral nerve injury and might help deepen our understanding of the molecular mechanisms underlying peripheral nerve regeneration.
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Affiliation(s)
- Lili Zhao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.,State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, Nanjing, China
| | - Sheng Yi
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
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167
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Modur V, Singh N, Mohanty V, Chung E, Muhammad B, Choi K, Chen X, Chetal K, Ratner N, Salomonis N, Weirauch MT, Waltz S, Huang G, Privette-Vinnedge L, Park JS, Janssen EM, Komurov K. Defective transcription elongation in a subset of cancers confers immunotherapy resistance. Nat Commun 2018; 9:4410. [PMID: 30353012 PMCID: PMC6199328 DOI: 10.1038/s41467-018-06810-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 09/21/2018] [Indexed: 12/13/2022] Open
Abstract
The nature and role of global transcriptional deregulations in cancers are not fully understood. We report that a large proportion of cancers have widespread defects in mRNA transcription elongation (TE). Cancers with TE defects (TEdeff) display spurious transcription and defective mRNA processing of genes characterized by long genomic length, poised promoters and inducible expression. Signaling pathways regulated by such genes, such as pro-inflammatory response pathways, are consistently suppressed in TEdeff tumors. Remarkably, TEdeff correlates with the poor response and outcome in immunotherapy, but not chemo- or targeted therapy, -treated renal cell carcinoma and metastatic melanoma patients. Forced pharmacologic or genetic induction of TEdeff in tumor cells impairs pro-inflammatory response signaling, and imposes resistance to the innate and adaptive anti-tumor immune responses and checkpoint inhibitor therapy in vivo. Therefore, defective TE is a previously unknown mechanism of tumor immune resistance, and should be assessed in cancer patients undergoing immunotherapy.
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Affiliation(s)
- Vishnu Modur
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA
| | - Navneet Singh
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA
| | - Vakul Mohanty
- University of Cincinnati Graduate Program in Systems Biology and Physiology, Cincinnati, 45267, OH, USA
| | - Eunah Chung
- Division of Developmental Biology, CCHMC, Cincinnati, 45229, OH, USA
- Division of Pediatric Urology, New York, NY, USA
| | - Belal Muhammad
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA
| | - Kwangmin Choi
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA
| | - Xiaoting Chen
- Center for Autoimmune Genomics and Etiology, CCHMC, Cincinnati, 45229, OH, USA
| | - Kashish Chetal
- Division of Biomedical Informatics, CCHMC, Cincinnati, 45229, OH, USA
| | - Nancy Ratner
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA
| | - Nathan Salomonis
- Division of Biomedical Informatics, CCHMC, Cincinnati, 45229, OH, USA
| | - Matthew T Weirauch
- Division of Developmental Biology, CCHMC, Cincinnati, 45229, OH, USA
- Center for Autoimmune Genomics and Etiology, CCHMC, Cincinnati, 45229, OH, USA
- Division of Biomedical Informatics, CCHMC, Cincinnati, 45229, OH, USA
| | - Susan Waltz
- Departments of Cancer Biology and Research Service, University of Cincinnati and Cincinnati Veteran's Hospital Medical Center, Cincinnati, 45267, OH, USA
| | - Gang Huang
- Division of Pathology, CCHMC, Cincinnati, 45229, OH, USA
| | | | - Joo-Seop Park
- Division of Developmental Biology, CCHMC, Cincinnati, 45229, OH, USA
- Division of Pediatric Urology, New York, NY, USA
| | - Edith M Janssen
- Division of Immunobiology, CCHMC, Cincinnati, 45229, OH, USA
| | - Kakajan Komurov
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center (CCHMC), Cincinnati, 45229, OH, USA.
- Division of Biomedical Informatics, CCHMC, Cincinnati, 45229, OH, USA.
- Division of Human Genetics, CCHMC, Cincinnati, 45229, OH, USA.
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168
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Cifani P, Dhabaria A, Chen Z, Yoshimi A, Kawaler E, Abdel-Wahab O, Poirier JT, Kentsis A. ProteomeGenerator: A Framework for Comprehensive Proteomics Based on de Novo Transcriptome Assembly and High-Accuracy Peptide Mass Spectral Matching. J Proteome Res 2018; 17:3681-3692. [PMID: 30295032 DOI: 10.1021/acs.jproteome.8b00295] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Modern mass spectrometry now permits genome-scale and quantitative measurements of biological proteomes. However, analysis of specific specimens is currently hindered by the incomplete representation of biological variability of protein sequences in canonical reference proteomes and the technical demands for their construction. Here, we report ProteomeGenerator, a framework for de novo and reference-assisted proteogenomic database construction and analysis based on sample-specific transcriptome sequencing and high-accuracy mass spectrometry proteomics. This enables the assembly of proteomes encoded by actively transcribed genes, including sample-specific protein isoforms resulting from non-canonical mRNA transcription, splicing, or editing. To improve the accuracy of protein isoform identification in non-canonical proteomes, ProteomeGenerator relies on statistical target-decoy database matching calibrated using sample-specific controls. Its current implementation includes automatic integration with MaxQuant mass spectrometry proteomics algorithms. We applied this method for the proteogenomic analysis of splicing factor SRSF2 mutant leukemia cells, demonstrating high-confidence identification of non-canonical protein isoforms arising from alternative transcriptional start sites, intron retention, and cryptic exon splicing as well as improved accuracy of genome-scale proteome discovery. Additionally, we report proteogenomic performance metrics for current state-of-the-art implementations of SEQUEST HT, MaxQuant, Byonic, and PEAKS mass spectral analysis algorithms. Finally, ProteomeGenerator is implemented as a Snakemake workflow within a Singularity container for one-step installation in diverse computing environments, thereby enabling open, scalable, and facile discovery of sample-specific, non-canonical, and neomorphic biological proteomes.
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Affiliation(s)
- Paolo Cifani
- Molecular Pharmacology Program , Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center , New York City , New York 10065 , United States
| | - Avantika Dhabaria
- Molecular Pharmacology Program , Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center , New York City , New York 10065 , United States
| | - Zining Chen
- Molecular Pharmacology Program , Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center , New York City , New York 10065 , United States
| | | | | | - Omar Abdel-Wahab
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology , New York University Langone Health , New York City , New York 10016 , United States
| | - John T Poirier
- Molecular Pharmacology Program , Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center , New York City , New York 10065 , United States.,Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology , New York University Langone Health , New York City , New York 10016 , United States
| | - Alex Kentsis
- Molecular Pharmacology Program , Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center , New York City , New York 10065 , United States.,Departments of Pediatrics, Pharmacology, and Physiology & Biophysics, Weill Cornell Medical College , Cornell University , New York , New York 10065 , United States
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169
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Xiang Y, Ye Y, Zhang Z, Han L. Maximizing the Utility of Cancer Transcriptomic Data. Trends Cancer 2018; 4:823-837. [PMID: 30470304 DOI: 10.1016/j.trecan.2018.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/23/2018] [Accepted: 09/24/2018] [Indexed: 12/13/2022]
Abstract
Transcriptomic profiling has been applied to large numbers of cancer samples, by large-scale consortia, including The Cancer Genome Atlas, International Cancer Genome Consortium, and Cancer Cell Line Encyclopedia. Advances in mining cancer transcriptomic data enable us to understand the endless complexity of the cancer transcriptome and thereby to discover new biomarkers and therapeutic targets. In this paper, we review computational resources for deep mining of transcriptomic data to identify, quantify, and determine the functional effects and clinical utility of transcriptomic events, including noncoding RNAs, post-transcriptional regulation, exogenous RNAs, and transcribed genetic variants. These approaches can be applied to other complex diseases, thereby greatly leveraging the impact of this work.
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Affiliation(s)
- Yu Xiang
- Department of Biochemistry and Molecular Biology, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; These authors contributed equally
| | - Youqiong Ye
- Department of Biochemistry and Molecular Biology, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; These authors contributed equally
| | - Zhao Zhang
- Department of Biochemistry and Molecular Biology, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Leng Han
- Department of Biochemistry and Molecular Biology, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Center for Precision Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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170
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Hacken ET, Valentin R, Regis FFD, Sun J, Yin S, Werner L, Deng J, Gruber M, Wong J, Zheng M, Gill AL, Seiler M, Smith P, Thomas M, Buonamici S, Ghia EM, Kim E, Rassenti LZ, Burger JA, Kipps TJ, Meyerson ML, Bachireddy P, Wang L, Reed R, Neuberg D, Carrasco RD, Brooks AN, Letai A, Davids MS, Wu CJ. Splicing modulation sensitizes chronic lymphocytic leukemia cells to venetoclax by remodeling mitochondrial apoptotic dependencies. JCI Insight 2018; 3:121438. [PMID: 30282833 PMCID: PMC6237462 DOI: 10.1172/jci.insight.121438] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/29/2018] [Indexed: 12/30/2022] Open
Abstract
The identification of targetable vulnerabilities in the context of therapeutic resistance is a key challenge in cancer treatment. We detected pervasive aberrant splicing as a characteristic feature of chronic lymphocytic leukemia (CLL), irrespective of splicing factor mutation status, which was associated with sensitivity to the spliceosome modulator, E7107. Splicing modulation affected CLL survival pathways, including members of the B cell lymphoma-2 (BCL2) family of proteins, remodeling antiapoptotic dependencies of human and murine CLL cells. E7107 treatment decreased myeloid cell leukemia-1 (MCL1) dependence and increased BCL2 dependence, sensitizing primary human CLL cells and venetoclax-resistant CLL-like cells from an Eμ-TCL1-based adoptive transfer murine model to treatment with the BCL2 inhibitor venetoclax. Our data provide preclinical rationale to support the combination of venetoclax with splicing modulators to reprogram apoptotic dependencies in CLL for treating venetoclax-resistant CLL cases.
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Affiliation(s)
- Elisa ten Hacken
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Rebecca Valentin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Fara Faye D. Regis
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jing Sun
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Shanye Yin
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Lillian Werner
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jing Deng
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Michaela Gruber
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Jessica Wong
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Mei Zheng
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Amy L. Gill
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | | | - Peter Smith
- H3 Biomedicine Inc., Cambridge, Massachusetts, USA
| | | | | | - Emanuela M. Ghia
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Ekaterina Kim
- University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Laura Z. Rassenti
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Jan A. Burger
- University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Thomas J. Kipps
- Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Matthew L. Meyerson
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute, Cambridge, Massachusetts, USA
| | - Pavan Bachireddy
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Lili Wang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Robin Reed
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Donna Neuberg
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Ruben D. Carrasco
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA.,Department of Oncologic Pathology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Angela N. Brooks
- Department of Biomolecular Engineering, University of California, Santa Cruz, California, USA
| | - Anthony Letai
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Matthew S. Davids
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Catherine J. Wu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute, Cambridge, Massachusetts, USA.,Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
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171
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El Marabti E, Younis I. The Cancer Spliceome: Reprograming of Alternative Splicing in Cancer. Front Mol Biosci 2018; 5:80. [PMID: 30246013 PMCID: PMC6137424 DOI: 10.3389/fmolb.2018.00080] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/09/2018] [Indexed: 12/15/2022] Open
Abstract
Alternative splicing allows for the expression of multiple RNA and protein isoforms from one gene, making it a major contributor to transcriptome and proteome diversification in eukaryotes. Advances in next generation sequencing technologies and genome-wide analyses have recently underscored the fact that the vast majority of multi-exon genes under normal physiology engage in alternative splicing in tissue-specific and developmental-specific manner. On the other hand, cancer cells exhibit remarkable transcriptome alterations partly by adopting cancer-specific splicing isoforms. These isoforms and their encoded proteins are not insignificant byproducts of the abnormal physiology of cancer cells, but either drivers of cancer progression or small but significant contributors to specific cancer hallmarks. Thus, it is paramount that the pathways that regulate alternative splicing in cancer, including the splicing factors that bind to pre-mRNAs and modulate spliceosome recruitment. In this review, we present a few distinct cases of alternative splicing in cancer, with an emphasis on their regulation as well as their contribution to cancer cell phenotype. Several categories of splicing aberrations are highlighted, including alterations in cancer-related genes that directly affect their pre-mRNA splicing, mutations in genes encoding splicing factors or core spliceosomal subunits, and the seemingly mutation-free disruptions in the balance of the expression of RNA-binding proteins, including components of both the major (U2-dependent) and minor (U12-dependent) spliceosomes. Given that the latter two classes cause global alterations in splicing that affect a wide range of genes, it remains a challenge to identify the ones that contribute to cancer progression. These challenges necessitate a systematic approach to decipher these aberrations and their impact on cancer. Ultimately, a sufficient understanding of splicing deregulation in cancer is predicted to pave the way for novel and innovative RNA-based therapies.
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Affiliation(s)
- Ettaib El Marabti
- Biological Sciences Program, Carnegie Mellon University in Qatar, Doha, Qatar
| | - Ihab Younis
- Biological Sciences Program, Carnegie Mellon University in Qatar, Doha, Qatar
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172
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JUM is a computational method for comprehensive annotation-free analysis of alternative pre-mRNA splicing patterns. Proc Natl Acad Sci U S A 2018; 115:E8181-E8190. [PMID: 30104386 DOI: 10.1073/pnas.1806018115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Alternative pre-mRNA splicing (AS) greatly diversifies metazoan transcriptomes and proteomes and is crucial for gene regulation. Current computational analysis methods of AS from Illumina RNA-sequencing data rely on preannotated libraries of known spliced transcripts, which hinders AS analysis with poorly annotated genomes and can further mask unknown AS patterns. To address this critical bioinformatics problem, we developed a method called the junction usage model (JUM) that uses a bottom-up approach to identify, analyze, and quantitate global AS profiles without any prior transcriptome annotations. JUM accurately reports global AS changes in terms of the five conventional AS patterns and an additional "composite" category composed of inseparable combinations of conventional patterns. JUM stringently classifies the difficult and disease-relevant pattern of intron retention (IR), reducing the false positive rate of IR detection commonly seen in other annotation-based methods to near-negligible rates. When analyzing AS in RNA samples derived from Drosophila heads, human tumors, and human cell lines bearing cancer-associated splicing factor mutations, JUM consistently identified approximately twice the number of novel AS events missed by other methods. Computational simulations showed JUM exhibits a 1.2 to 4.8 times higher true positive rate at a fixed cutoff of 5% false discovery rate. In summary, JUM provides a framework and improved method that removes the necessity for transcriptome annotations and enables the detection, analysis, and quantification of AS patterns in complex metazoan transcriptomes with superior accuracy.
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173
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Anufrieva KS, Shender VО, Arapidi GP, Pavlyukov MS, Shakhparonov MI, Shnaider PV, Butenko IO, Lagarkova MA, Govorun VM. Therapy-induced stress response is associated with downregulation of pre-mRNA splicing in cancer cells. Genome Med 2018; 10:49. [PMID: 29950180 PMCID: PMC6020472 DOI: 10.1186/s13073-018-0557-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Accepted: 06/07/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Abnormal pre-mRNA splicing regulation is common in cancer, but the effects of chemotherapy on this process remain unclear. METHODS To evaluate the effect of chemotherapy on slicing regulation, we performed meta-analyses of previously published transcriptomic, proteomic, phosphoproteomic, and secretome datasets. Our findings were verified by LC-MS/MS, western blotting, immunofluorescence, and FACS analyses of multiple cancer cell lines treated with cisplatin and pladienolide B. RESULTS Our results revealed that different types of chemotherapy lead to similar changes in alternative splicing by inducing intron retention in multiple genes. To determine the mechanism underlying this effect, we analyzed gene expression in 101 cell lines affected by ɣ-irradiation, hypoxia, and 10 various chemotherapeutic drugs. Strikingly, оnly genes involved in the cell cycle and pre-mRNA splicing regulation were changed in a similar manner in all 335 tested samples regardless of stress stimuli. We revealed significant downregulation of gene expression levels in these two pathways, which could be explained by the observed decrease in splicing efficiency and global intron retention. We showed that the levels of active spliceosomal proteins might be further post-translationally decreased by phosphorylation and export into the extracellular space. To further explore these bioinformatics findings, we performed proteomic analysis of cisplatin-treated ovarian cancer cells. Finally, we demonstrated that the splicing inhibitor pladienolide B impairs the cellular response to DNA damage and significantly increases the sensitivity of cancer cells to chemotherapy. CONCLUSIONS Decreased splicing efficiency and global intron retention is a novel stress response mechanism that may promote survival of malignant cells following therapy. We found that this mechanism can be inhibited by pladienolide B, which significantly increases the sensitivity of cancer cells to cisplatin which makes it a good candidate drug for improving the efficiency of cancer therapy.
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Affiliation(s)
- Ksenia S Anufrieva
- Laboratory of Proteomics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia.
- Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia.
- Systems Biology Lab, Moscow Institute of Physics and Technology (State University), Moscow, Region, 141701, Russia.
| | - Victoria О Shender
- Laboratory of Proteomics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia.
- Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia.
| | - Georgij P Arapidi
- Laboratory of Proteomics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia
- Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
- Systems Biology Lab, Moscow Institute of Physics and Technology (State University), Moscow, Region, 141701, Russia
| | - Marat S Pavlyukov
- Laboratory of Membrane Bioenergetics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia
| | - Michail I Shakhparonov
- Laboratory of Membrane Bioenergetics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia
| | - Polina V Shnaider
- Laboratory of Proteomics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia
- Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Ivan O Butenko
- Laboratory of Proteomic Analysis, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Maria A Lagarkova
- Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Vadim M Govorun
- Laboratory of Proteomics, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, 117997, Russia
- Laboratory of Proteomic Analysis, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
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174
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Nuclear PTEN safeguards pre-mRNA splicing to link Golgi apparatus for its tumor suppressive role. Nat Commun 2018; 9:2392. [PMID: 29921876 PMCID: PMC6008332 DOI: 10.1038/s41467-018-04760-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 05/21/2018] [Indexed: 12/11/2022] Open
Abstract
Dysregulation of pre-mRNA alternative splicing (AS) is closely associated with cancers. However, the relationships between the AS and classic oncogenes/tumor suppressors are largely unknown. Here we show that the deletion of tumor suppressor PTEN alters pre-mRNA splicing in a phosphatase-independent manner, and identify 262 PTEN-regulated AS events in 293T cells by RNA sequencing, which are associated with significant worse outcome of cancer patients. Based on these findings, we report that nuclear PTEN interacts with the splicing machinery, spliceosome, to regulate its assembly and pre-mRNA splicing. We also identify a new exon 2b in GOLGA2 transcript and the exon exclusion contributes to PTEN knockdown-induced tumorigenesis by promoting dramatic Golgi extension and secretion, and PTEN depletion significantly sensitizes cancer cells to secretion inhibitors brefeldin A and golgicide A. Our results suggest that Golgi secretion inhibitors alone or in combination with PI3K/Akt kinase inhibitors may be therapeutically useful for PTEN-deficient cancers.
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175
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Keller M, Hu Y, Mesihovic A, Fragkostefanakis S, Schleiff E, Simm S. Alternative splicing in tomato pollen in response to heat stress. DNA Res 2018; 24:205-217. [PMID: 28025318 PMCID: PMC5397606 DOI: 10.1093/dnares/dsw051] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 10/26/2016] [Indexed: 01/08/2023] Open
Abstract
Alternative splicing (AS) is a key control mechanism influencing signal response cascades in different developmental stages and under stress conditions. In this study, we examined heat stress (HS)-induced AS in the heat sensitive pollen tissue of two tomato cultivars. To obtain the entire spectrum of HS-related AS, samples taken directly after HS and after recovery were combined and analysed by RNA-seq. For nearly 9,200 genes per cultivar, we observed at least one AS event under HS. In comparison to control, for one cultivar we observed 76% more genes with intron retention (IR) or exon skipping (ES) under HS. Furthermore, 2,343 genes had at least one transcript with IR or ES accumulated under HS in both cultivars. These genes are involved in biological processes like protein folding, gene expression and heat response. Transcriptome assembly of these genes revealed that most of the alternative spliced transcripts possess truncated coding sequences resulting in partial or total loss of functional domains. Moreover, 141 HS specific and 22 HS repressed transcripts were identified. Further on, we propose AS as layer of stress response regulating constitutively expressed genes under HS by isoform abundance.
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Affiliation(s)
- Mario Keller
- Department of Biosciences, Molecular Cell Biology of Plants
| | - Yangjie Hu
- Department of Biosciences, Molecular Cell Biology of Plants
| | | | | | - Enrico Schleiff
- Department of Biosciences, Molecular Cell Biology of Plants.,Cluster of Excellence Frankfurt.,Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, D-60438 Frankfurt am Main, Germany
| | - Stefan Simm
- Department of Biosciences, Molecular Cell Biology of Plants.,Cluster of Excellence Frankfurt
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176
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Lin SY, Chooi YH, Solomon PS. The global regulator of pathogenesis PnCon7 positively regulates Tox3 effector gene expression through direct interaction in the wheat pathogen Parastagonospora nodorum. Mol Microbiol 2018; 109:78-90. [PMID: 29722915 DOI: 10.1111/mmi.13968] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2018] [Indexed: 01/24/2023]
Abstract
To investigate effector gene regulation in the wheat pathogenic fungus Parastagonospora nodorum, the promoter and expression of Tox3 was characterised through a series of complementary approaches. Promoter deletion and DNase I footprinting experiments identified a 25 bp region in the Tox3 promoter as being required for transcription. Subsequent yeast one-hybrid analysis using the DNA sequence as bait identified that interacting partner as the C2H2 zinc finger transcription factor PnCon7, a putative master regulator of pathogenesis. Silencing of PnCon7 resulted in the down-regulation of Tox3 demonstrating that the transcription factor has a positive regulatory role on gene expression. Analysis of Tox3 expression in the PnCon7 silenced strains revealed a strong correlation with PnCon7 transcript levels, supportive of a direct regulatory role. Subsequent pathogenicity assays using PnCon7-silenced isolates revealed that the transcription factor was required for Tox3-mediated disease. The expression of two other necrotrophic effectors (ToxA and Tox1) was also affected but in a non-dose dependent manner suggesting that the regulatory role of PnCon7 on these genes was indirect. Collectively, these data have advanced our fundamental understanding of the Con7 master regulator of pathogenesis by demonstrating its positive regulatory role on the Tox3 effector in P. nodorum through direct interaction.
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Affiliation(s)
- Shao-Yu Lin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Yit-Heng Chooi
- School of Molecular Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
| | - Peter S Solomon
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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177
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Pineda JMB, Bradley RK. Most human introns are recognized via multiple and tissue-specific branchpoints. Genes Dev 2018; 32:577-591. [PMID: 29666160 PMCID: PMC5959240 DOI: 10.1101/gad.312058.118] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/09/2018] [Indexed: 12/20/2022]
Abstract
Pineda and Bradley demonstrate that almost all human introns contain multiple branchpoints. Approximately three-quarters of constitutive introns exhibit tissue-specific branchpoint usage. Although branchpoint recognition is an essential component of intron excision during the RNA splicing process, the branchpoint itself is frequently assumed to be a basal, rather than regulatory, sequence feature. However, this assumption has not been systematically tested due to the technical difficulty of identifying branchpoints and quantifying their usage. Here, we analyzed ∼1.31 trillion reads from 17,164 RNA sequencing data sets to demonstrate that almost all human introns contain multiple branchpoints. This complexity holds even for constitutive introns, 95% of which contain multiple branchpoints, with an estimated five to six branchpoints per intron. Introns upstream of the highly regulated ultraconserved poison exons of SR genes contain twice as many branchpoints as the genomic average. Approximately three-quarters of constitutive introns exhibit tissue-specific branchpoint usage. In an extreme example, we observed a complete switch in branchpoint usage in the well-studied first intron of HBB (β-globin) in normal bone marrow versus metastatic prostate cancer samples. Our results indicate that the recognition of most introns is unexpectedly complex and tissue-specific and suggest that alternative splicing catalysis typifies the majority of introns even in the absence of differences in the mature mRNA.
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Affiliation(s)
- Jose Mario Bello Pineda
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Department of Genome Sciences, University of Washington, Seattle, Wasington 98195, USA.,Medical Scientist Training Program, University of Washington, Seattle, Wasington 98195, USA
| | - Robert K Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.,Department of Genome Sciences, University of Washington, Seattle, Wasington 98195, USA
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178
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Rekosh D, Hammarskjold ML. Intron retention in viruses and cellular genes: Detention, border controls and passports. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1470. [PMID: 29508942 DOI: 10.1002/wrna.1470] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/04/2018] [Accepted: 01/24/2018] [Indexed: 02/06/2023]
Abstract
Intron retention (IR), where one or more introns remain in the RNA after splicing, was long thought to be rare in mammalian cells, albeit common in plants and some viruses. Largely due to the development of better methods for RNA analysis, it has now been recognized that IR is much more common than previously thought and that this mechanism is likely to play an important role in mammalian gene regulation. To date, most publications and reviews about IR have described the resulting mRNAs as "dead end" products, with no direct consequence for the proteome. However, there are also many reports of mRNAs with retained introns giving rise to alternative protein isoforms. Although this was originally revealed in viral systems, there are now numerous examples of bona fide cellular proteins that are translated from mRNAs with retained introns. These new isoforms have sometimes been shown to have important regulatory functions. In this review, we highlight recent developments in this area and the research on viruses that led the way to the realization of the many ways in which mRNAs with retained introns can be regulated. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing RNA Export and Localization > Nuclear Export/Import RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.
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Affiliation(s)
- David Rekosh
- The Myles H. Thaler Center for AIDS and Human Retrovirus Research and the Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, Virginia.,Department of Microbiology, University of Venda, Thohoyandou, South Africa
| | - Marie-Louise Hammarskjold
- The Myles H. Thaler Center for AIDS and Human Retrovirus Research and the Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, Virginia.,Department of Microbiology, University of Venda, Thohoyandou, South Africa
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179
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Splicing dysfunction and disease: The case of granulopoiesis. Semin Cell Dev Biol 2018; 75:23-39. [DOI: 10.1016/j.semcdb.2017.08.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/28/2017] [Accepted: 08/28/2017] [Indexed: 12/20/2022]
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180
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Vanichkina DP, Schmitz U, Wong JJL, Rasko JE. Challenges in defining the role of intron retention in normal biology and disease. Semin Cell Dev Biol 2018; 75:40-49. [DOI: 10.1016/j.semcdb.2017.07.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/19/2017] [Accepted: 07/19/2017] [Indexed: 10/19/2022]
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181
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Wong ACH, Rasko JEJ, Wong JJL. We skip to work: alternative splicing in normal and malignant myelopoiesis. Leukemia 2018; 32:1081-1093. [DOI: 10.1038/s41375-018-0021-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/14/2017] [Accepted: 12/22/2017] [Indexed: 12/15/2022]
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182
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Kim D, Shivakumar M, Han S, Sinclair MS, Lee YJ, Zheng Y, Olopade OI, Kim D, Lee Y. Population-dependent Intron Retention and DNA Methylation in Breast Cancer. Mol Cancer Res 2018; 16:461-469. [PMID: 29330282 DOI: 10.1158/1541-7786.mcr-17-0227] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 09/15/2017] [Accepted: 11/27/2017] [Indexed: 12/31/2022]
Abstract
Regulation of gene expression by DNA methylation in gene promoter regions is well studied; however, the effects of methylation in the gene body (exons and introns) on gene expression are comparatively understudied. Recently, hypermethylation has been implicated in the inclusion of alternatively spliced exons; moreover, exon recognition can be enhanced by recruiting the methyl-CpG-binding protein (MeCP2) to hypermethylated sites. This study examines whether the methylation status of an intron is correlated with how frequently the intron is retained during splicing using DNA methylation and RNA sequencing data from breast cancer tissue specimens in The Cancer Genome Atlas. Interestingly, hypomethylation of introns is correlated with higher levels of intron expression in mRNA and the methylation level of an intron is inversely correlated with its retention in mRNA from the gene in which it is located. Furthermore, significant population differences were observed in the methylation level of retained introns. In African-American donors, retained introns were not only less methylated compared to European-American donors, but also were more highly expressed. This underscores the need for understanding epigenetic differences in populations and their correlation with breast cancer is an important step toward achieving personalized cancer care.Implications: This research contributes to the understanding of how epigenetic markers in the gene body communicate with the transcriptional machinery to control transcript diversity and differential biological response to changes in methylation status could underlie some of the known, yet unexplained, disparities in certain breast cancer patient populations. Mol Cancer Res; 16(3); 461-9. ©2018 AACR.
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Affiliation(s)
- Dongwook Kim
- Department of Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Manu Shivakumar
- Department of Biomedical and Translational Informatics, Geisinger Health System, Danville, Pennsylvania
| | - Seonggyun Han
- Department of Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Michael S Sinclair
- Department of Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Young-Ji Lee
- Department of Health and Community Systems, University of Pittsburgh School of Nursing, Pittsburgh, Pennsylvania
| | - Yonglan Zheng
- Department of Medicine, University of Chicago, Chicago, Illinois
| | | | - Dokyoon Kim
- Department of Biomedical and Translational Informatics, Geisinger Health System, Danville, Pennsylvania.
- The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania
| | - Younghee Lee
- Department of Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, Utah.
- Huntsman Cancer Institute, Salt Lake City, Utah
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183
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Filichkin SA, Hamilton M, Dharmawardhana PD, Singh SK, Sullivan C, Ben-Hur A, Reddy ASN, Jaiswal P. Abiotic Stresses Modulate Landscape of Poplar Transcriptome via Alternative Splicing, Differential Intron Retention, and Isoform Ratio Switching. FRONTIERS IN PLANT SCIENCE 2018; 9:5. [PMID: 29483921 PMCID: PMC5816337 DOI: 10.3389/fpls.2018.00005] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/03/2018] [Indexed: 05/19/2023]
Abstract
Abiotic stresses affect plant physiology, development, growth, and alter pre-mRNA splicing. Western poplar is a model woody tree and a potential bioenergy feedstock. To investigate the extent of stress-regulated alternative splicing (AS), we conducted an in-depth survey of leaf, root, and stem xylem transcriptomes under drought, salt, or temperature stress. Analysis of approximately one billion of genome-aligned RNA-Seq reads from tissue- or stress-specific libraries revealed over fifteen millions of novel splice junctions. Transcript models supported by both RNA-Seq and single molecule isoform sequencing (Iso-Seq) data revealed a broad array of novel stress- and/or tissue-specific isoforms. Analysis of Iso-Seq data also resulted in the discovery of 15,087 novel transcribed regions of which 164 show AS. Our findings demonstrate that abiotic stresses profoundly perturb transcript isoform profiles and trigger widespread intron retention (IR) events. Stress treatments often increased or decreased retention of specific introns - a phenomenon described here as differential intron retention (DIR). Many differentially retained introns were regulated in a stress- and/or tissue-specific manner. A subset of transcripts harboring super stress-responsive DIR events showed persisting fluctuations in the degree of IR across all treatments and tissue types. To investigate coordinated dynamics of intron-containing transcripts in the study we quantified absolute copy number of isoforms of two conserved transcription factors (TFs) using Droplet Digital PCR. This case study suggests that stress treatments can be associated with coordinated switches in relative ratios between fully spliced and intron-retaining isoforms and may play a role in adjusting transcriptome to abiotic stresses.
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Affiliation(s)
- Sergei A. Filichkin
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Michael Hamilton
- Department of Computer Science, Colorado State University, Fort Collins, CO, United States
| | | | - Sunil K. Singh
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Christopher Sullivan
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, OR, United States
| | - Asa Ben-Hur
- Department of Computer Science, Colorado State University, Fort Collins, CO, United States
| | - Anireddy S. N. Reddy
- Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, United States
| | - Pankaj Jaiswal
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
- *Correspondence: Pankaj Jaiswal,
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184
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Therapeutic Applications of Targeted Alternative Splicing to Cancer Treatment. Int J Mol Sci 2017; 19:ijms19010075. [PMID: 29283381 PMCID: PMC5796025 DOI: 10.3390/ijms19010075] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 12/22/2017] [Accepted: 12/24/2017] [Indexed: 12/16/2022] Open
Abstract
A growing body of studies has documented the pathological influence of impaired alternative splicing (AS) events on numerous diseases, including cancer. In addition, the generation of alternatively spliced isoforms is frequently noted to result in drug resistance in many cancer therapies. To gain comprehensive insights into the impacts of AS events on cancer biology and therapeutic developments, this paper highlights recent findings regarding the therapeutic routes of targeting alternative-spliced isoforms and splicing regulators to treatment strategies for distinct cancers.
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185
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The Y Chromosome Modulates Splicing and Sex-Biased Intron Retention Rates in Drosophila. Genetics 2017; 208:1057-1067. [PMID: 29263027 DOI: 10.1534/genetics.117.300637] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/18/2017] [Indexed: 01/01/2023] Open
Abstract
The Drosophila Y chromosome is a 40-Mb segment of mostly repetitive DNA; it harbors a handful of protein-coding genes and a disproportionate amount of satellite repeats, transposable elements, and multicopy DNA arrays. Intron retention (IR) is a type of alternative splicing (AS) event by which one or more introns remain within the mature transcript. IR recently emerged as a deliberate cellular mechanism to modulate gene expression levels and has been implicated in multiple biological processes. However, the extent of sex differences in IR and the contribution of the Y chromosome to the modulation of AS and IR rates has not been addressed. Here we showed pervasive IR in the fruit fly Drosophila melanogaster with thousands of novel IR events, hundreds of which displayed extensive sex bias. The data also revealed an unsuspected role for the Y chromosome in the modulation of AS and IR. The majority of sex-biased IR events introduced premature termination codons and the magnitude of sex bias was associated with gene expression differences between the sexes. Surprisingly, an extra Y chromosome in males (X^YY genotype) or the presence of a Y chromosome in females (X^XY genotype) significantly modulated IR and recapitulated natural differences in IR between the sexes. Our results highlight the significance of sex-biased IR in tuning sex differences and the role of the Y chromosome as a source of variable IR rates between the sexes. Modulation of splicing and IR rates across the genome represent new and unexpected outcomes of the Drosophila Y chromosome.
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186
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Jyotsana N, Heuser M. Exploiting differential RNA splicing patterns: a potential new group of therapeutic targets in cancer. Expert Opin Ther Targets 2017; 22:107-121. [PMID: 29235382 DOI: 10.1080/14728222.2018.1417390] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Mutations in genes associated with splicing have been found in hematologic malignancies, but also in solid cancers. Aberrant cancer specific RNA splicing either results from mutations or misexpression of the spliceosome genes directly, or from mutations in splice sites of oncogenes or tumor suppressors. Areas covered: In this review, we present molecular targets of aberrant splicing in various malignancies, information on existing and emerging therapeutics against such targets, and strategies for future drug development. Expert opinion: Alternative splicing is an important mechanism that controls gene expression, and hence pharmacologic and genetic control of aberrant alternative RNA splicing has been proposed as a potential therapy in cancer. To identify and validate aberrant RNA splicing patterns as therapeutic targets we need to (1) characterize the most common genetic aberrations of the spliceosome and of splice sites, (2) understand the dysregulated downstream pathways and (3) exploit in-vivo disease models of aberrant splicing. Antisense oligonucleotides show promising activity, but will benefit from improved delivery tools. Inhibitors of mutated splicing factors require improved specificity, as alternative and aberrant splicing are often intertwined like two sides of the same coin. In summary, targeting aberrant splicing is an early but emerging field in cancer treatment.
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Affiliation(s)
- Nidhi Jyotsana
- a Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation , Hannover Medical School , Hannover , Germany
| | - Michael Heuser
- a Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation , Hannover Medical School , Hannover , Germany
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187
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Comparative Analysis and Classification of Cassette Exons and Constitutive Exons. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7323508. [PMID: 29349080 PMCID: PMC5734011 DOI: 10.1155/2017/7323508] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/13/2017] [Indexed: 12/11/2022]
Abstract
Alternative splicing (AS) is a major engine that drives proteome diversity in mammalian genomes and is a widespread cause of human hereditary diseases. More than 95% of genes in the human genome are alternatively spliced, and the most common type of AS is the cassette exon. Recent discoveries have demonstrated that the cassette exon plays an important role in genetic diseases. To discover the formation mechanism of cassette exon events, we statistically analyze cassette exons and find that cassette exon events are strongly influenced by individual exons that are smaller in size and that have a lower GC content, more codon terminations, and weaker splice sites. We propose an improved random-forest-based hybrid method of distinguishing cassette exons from constitutive exons. Our method achieves a high accuracy in classifying cassette exons and constitutive exons and is verified to outperform previous approaches. It is anticipated that this study will facilitate a better understanding of the underlying mechanisms in cassette exons.
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188
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Schmitz U, Pinello N, Jia F, Alasmari S, Ritchie W, Keightley MC, Shini S, Lieschke GJ, Wong JJL, Rasko JEJ. Intron retention enhances gene regulatory complexity in vertebrates. Genome Biol 2017; 18:216. [PMID: 29141666 PMCID: PMC5688624 DOI: 10.1186/s13059-017-1339-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 10/13/2017] [Indexed: 01/22/2023] Open
Abstract
Background While intron retention (IR) is now widely accepted as an important mechanism of mammalian gene expression control, it remains the least studied form of alternative splicing. To delineate conserved features of IR, we performed an exhaustive phylogenetic analysis in a highly purified and functionally defined cell type comprising neutrophilic granulocytes from five vertebrate species spanning 430 million years of evolution. Results Our RNA-sequencing-based analysis suggests that IR increases gene regulatory complexity, which is indicated by a strong anti-correlation between the number of genes affected by IR and the number of protein-coding genes in the genome of individual species. Our results confirm that IR affects many orthologous or functionally related genes in granulocytes. Further analysis uncovers new and unanticipated conserved characteristics of intron-retaining transcripts. We find that intron-retaining genes are transcriptionally co-regulated from bidirectional promoters. Intron-retaining genes have significantly longer 3′ UTR sequences, with a corresponding increase in microRNA binding sites, some of which include highly conserved sequence motifs. This suggests that intron-retaining genes are highly regulated post-transcriptionally. Conclusions Our study provides unique insights concerning the role of IR as a robust and evolutionarily conserved mechanism of gene expression regulation. Our findings enhance our understanding of gene regulatory complexity by adding another contributor to evolutionary adaptation. Electronic supplementary material The online version of this article (doi:10.1186/s13059-017-1339-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ulf Schmitz
- Gene & Stem Cell Therapy Program, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia.,Sydney Medical School, University of Sydney, Camperdown, 2050, NSW, Australia
| | - Natalia Pinello
- Gene & Stem Cell Therapy Program, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia.,Sydney Medical School, University of Sydney, Camperdown, 2050, NSW, Australia.,Gene Regulation in Cancer Laboratory, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia
| | - Fangzhi Jia
- Gene & Stem Cell Therapy Program, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia.,Sydney Medical School, University of Sydney, Camperdown, 2050, NSW, Australia
| | - Sultan Alasmari
- Australian Regenerative Medicine Institute, Monash University, Clayton, 3800, VIC, Australia
| | | | | | - Shaniko Shini
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Graham J Lieschke
- Australian Regenerative Medicine Institute, Monash University, Clayton, 3800, VIC, Australia
| | - Justin J-L Wong
- Gene & Stem Cell Therapy Program, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia.,Sydney Medical School, University of Sydney, Camperdown, 2050, NSW, Australia.,Gene Regulation in Cancer Laboratory, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia
| | - John E J Rasko
- Gene & Stem Cell Therapy Program, Centenary Institute, University of Sydney, Camperdown, 2050, NSW, Australia. .,Sydney Medical School, University of Sydney, Camperdown, 2050, NSW, Australia. .,Cell and Molecular Therapies, Royal Prince Alfred Hospital, Camperdown, 2050, NSW, Australia. .,, Locked Bag 6, Newtown, NSW, 2042, Australia.
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189
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Agrawal AA, Yu L, Smith PG, Buonamici S. Targeting splicing abnormalities in cancer. Curr Opin Genet Dev 2017; 48:67-74. [PMID: 29136527 DOI: 10.1016/j.gde.2017.10.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 09/19/2017] [Accepted: 10/13/2017] [Indexed: 01/11/2023]
Abstract
Recently splicing has been recognized as a key pathway in cancer. Although aberrant splicing has been shown to be a consequence of mutations or the abnormal expression of splicing factors (trans-effect changes) or mutations in the splicing sequences (cis-effect mutations), the connections between aberrant splicing and cancer initiation or progression are still not well understood. Here we review the mutational landscape of splicing factors in cancer and associated splicing consequences, along with the most important examples of the therapeutic approaches targeting the spliceosome currently being investigated in oncology.
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Affiliation(s)
| | - Lihua Yu
- H3 Biomedicine, Inc., Cambridge, MA, USA
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190
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Kielkopf CL. Insights from structures of cancer-relevant pre-mRNA splicing factors. Curr Opin Genet Dev 2017; 48:57-66. [PMID: 29128695 DOI: 10.1016/j.gde.2017.10.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 10/10/2017] [Accepted: 10/13/2017] [Indexed: 12/21/2022]
Abstract
Pre-mRNA splicing factors recognize consensus signals within preliminary transcripts, and as cogs of the spliceosome machine, orchestrate the excision and rejoining of pre-mRNA regions for gene expression. Large-scale sequencing has demonstrated that mutations in key genes encoding pre-mRNA splicing factors are common among myeloid neoplasms and also occur in a variety of other cancers. This revelation offers new therapeutic opportunities to target pre-mRNA splicing vulnerabilities in hematologic and other malignancies. The mutated residues typically alter 3' splice site choice for a subset of transcripts. In this review, we highlight mechanistic insights from recent 3D structures that reveal the affected residues poised for pre-mRNA recognition.
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Affiliation(s)
- 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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191
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Rogawski DS, Vitanza NA, Gauthier AC, Ramaswamy V, Koschmann C. Integrating RNA sequencing into neuro-oncology practice. Transl Res 2017; 189:93-104. [PMID: 28746860 PMCID: PMC5659901 DOI: 10.1016/j.trsl.2017.06.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/27/2017] [Accepted: 06/30/2017] [Indexed: 12/22/2022]
Abstract
Malignant tumors of the central nervous system (CNS) cause substantial morbidity and mortality, yet efforts to optimize chemo- and radiotherapy have largely failed to improve dismal prognoses. Over the past decade, RNA sequencing (RNA-seq) has emerged as a powerful tool to comprehensively characterize the transcriptome of CNS tumor cells in one high-throughput step, leading to improved understanding of CNS tumor biology and suggesting new routes for targeted therapies. RNA-seq has been instrumental in improving the diagnostic classification of brain tumors, characterizing oncogenic fusion genes, and shedding light on intratumor heterogeneity. Currently, RNA-seq is beginning to be incorporated into regular neuro-oncology practice in the form of precision neuro-oncology programs, which use information from tumor sequencing to guide implementation of personalized targeted therapies. These programs show great promise in improving patient outcomes for tumors where single agent trials have been ineffective. As RNA-seq is a relatively new technique, many further applications yielding new advances in CNS tumor research and management are expected in the coming years.
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Affiliation(s)
- David S Rogawski
- Department of Pediatrics, University of Michigan School of Medicine, Ann Arbor, Mich
| | | | | | - Vijay Ramaswamy
- Division of Haematology/Oncology, Department of Pediatrics, Hospital for Sick Children, Toronto, ON, Canada
| | - Carl Koschmann
- Department of Pediatrics, University of Michigan School of Medicine, Ann Arbor, Mich.
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192
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Richards AL, Watza D, Findley A, Alazizi A, Wen X, Pai AA, Pique-Regi R, Luca F. Environmental perturbations lead to extensive directional shifts in RNA processing. PLoS Genet 2017; 13:e1006995. [PMID: 29023442 PMCID: PMC5667937 DOI: 10.1371/journal.pgen.1006995] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 11/02/2017] [Accepted: 08/21/2017] [Indexed: 02/06/2023] Open
Abstract
Environmental perturbations have large effects on both organismal and cellular traits, including gene expression, but the extent to which the environment affects RNA processing remains largely uncharacterized. Recent studies have identified a large number of genetic variants associated with variation in RNA processing that also have an important role in complex traits; yet we do not know in which contexts the different underlying isoforms are used. Here, we comprehensively characterized changes in RNA processing events across 89 environments in five human cell types and identified 15,300 event shifts (FDR = 15%) comprised of eight event types in over 4,000 genes. Many of these changes occur consistently in the same direction across conditions, indicative of global regulation by trans factors. Accordingly, we demonstrate that environmental modulation of splicing factor binding predicts shifts in intron retention, and that binding of transcription factors predicts shifts in alternative first exon (AFE) usage in response to specific treatments. We validated the mechanism hypothesized for AFE in two independent datasets. Using ATAC-seq, we found altered binding of 64 factors in response to selenium at sites of AFE shift, including ELF2 and other factors in the ETS family. We also performed AFE QTL mapping in 373 individuals and found an enrichment for SNPs predicted to disrupt binding of the ELF2 factor. Together, these results demonstrate that RNA processing is dramatically changed in response to environmental perturbations through specific mechanisms regulated by trans factors.
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Affiliation(s)
- Allison L. Richards
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (ALR); (AAP); (RPR); (FL)
| | - Donovan Watza
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
| | - Anthony Findley
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
| | - Adnan Alazizi
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
| | - Xiaoquan Wen
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Athma A. Pai
- RNA Therapeutics Institute, University of Massachusetts, Worcester, Massachusetts, United States of America
- * E-mail: (ALR); (AAP); (RPR); (FL)
| | - Roger Pique-Regi
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (ALR); (AAP); (RPR); (FL)
| | - Francesca Luca
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America
- Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (ALR); (AAP); (RPR); (FL)
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193
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Braun CJ, Stanciu M, Boutz PL, Patterson JC, Calligaris D, Higuchi F, Neupane R, Fenoglio S, Cahill DP, Wakimoto H, Agar NYR, Yaffe MB, Sharp PA, Hemann MT, Lees JA. Coordinated Splicing of Regulatory Detained Introns within Oncogenic Transcripts Creates an Exploitable Vulnerability in Malignant Glioma. Cancer Cell 2017; 32:411-426.e11. [PMID: 28966034 PMCID: PMC5929990 DOI: 10.1016/j.ccell.2017.08.018] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/05/2017] [Accepted: 08/30/2017] [Indexed: 01/22/2023]
Abstract
Glioblastoma (GBM) is a devastating malignancy with few therapeutic options. We identify PRMT5 in an in vivo GBM shRNA screen and show that PRMT5 knockdown or inhibition potently suppresses in vivo GBM tumors, including patient-derived xenografts. Pathway analysis implicates splicing in cellular PRMT5 dependency, and we identify a biomarker that predicts sensitivity to PRMT5 inhibition. We find that PRMT5 deficiency primarily disrupts the removal of detained introns (DIs). This impaired DI splicing affects proliferation genes, whose downregulation coincides with cell cycle defects, senescence and/or apoptosis. We further show that DI programs are evolutionarily conserved and operate during neurogenesis, suggesting that they represent a physiological regulatory mechanism. Collectively, these findings reveal a PRMT5-regulated DI-splicing program as an exploitable cancer vulnerability.
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Affiliation(s)
- Christian J Braun
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Monica Stanciu
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Paul L Boutz
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Jesse C Patterson
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - David Calligaris
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Fumi Higuchi
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Rachit Neupane
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Silvia Fenoglio
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Daniel P Cahill
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Hiroaki Wakimoto
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Nathalie Y R Agar
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA; Department of Radiology, Harvard Medical School, Boston, MA 02115, USA
| | - Michael B Yaffe
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Acute Care Surgery, Trauma, and Critical Care, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Phillip A Sharp
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Michael T Hemann
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
| | - Jacqueline A Lees
- The David H. Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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194
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Transcriptome analysis of developing lens reveals abundance of novel transcripts and extensive splicing alterations. Sci Rep 2017; 7:11572. [PMID: 28912564 PMCID: PMC5599659 DOI: 10.1038/s41598-017-10615-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 08/11/2017] [Indexed: 01/22/2023] Open
Abstract
Lens development involves a complex and highly orchestrated regulatory program. Here, we investigate the transcriptomic alterations and splicing events during mouse lens formation using RNA-seq data from multiple developmental stages, and construct a molecular portrait of known and novel transcripts. We show that the extent of novelty of expressed transcripts decreases significantly in post-natal lens compared to embryonic stages. Characterization of novel transcripts into partially novel transcripts (PNTs) and completely novel transcripts (CNTs) (novelty score ≥ 70%) revealed that the PNTs are both highly conserved across vertebrates and highly expressed across multiple stages. Functional analysis of PNTs revealed their widespread role in lens developmental processes while hundreds of CNTs were found to be widely expressed and predicted to encode for proteins. We verified the expression of four CNTs across stages. Examination of splice isoforms revealed skipped exon and retained intron to be the most abundant alternative splicing events during lens development. We validated by RT-PCR and Sanger sequencing, the predicted splice isoforms of several genes Banf1, Cdk4, Cryaa, Eif4g2, Pax6, and Rbm5. Finally, we present a splicing browser Eye Splicer (http://www.iupui.edu/~sysbio/eye-splicer/), to facilitate exploration of developmentally altered splicing events and to improve understanding of post-transcriptional regulatory networks during mouse lens development.
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195
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Brady LK, Wang H, Radens CM, Bi Y, Radovich M, Maity A, Ivan C, Ivan M, Barash Y, Koumenis C. Transcriptome analysis of hypoxic cancer cells uncovers intron retention in EIF2B5 as a mechanism to inhibit translation. PLoS Biol 2017; 15:e2002623. [PMID: 28961236 PMCID: PMC5636171 DOI: 10.1371/journal.pbio.2002623] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 10/11/2017] [Accepted: 09/07/2017] [Indexed: 01/09/2023] Open
Abstract
Cells adjust to hypoxic stress within the tumor microenvironment by downregulating energy-consuming processes including translation. To delineate mechanisms of cellular adaptation to hypoxia, we performed RNA-Seq of normoxic and hypoxic head and neck cancer cells. These data revealed a significant down regulation of genes known to regulate RNA processing and splicing. Exon-level analyses classified > 1,000 mRNAs as alternatively spliced under hypoxia and uncovered a unique retained intron (RI) in the master regulator of translation initiation, EIF2B5. Notably, this intron was expressed in solid tumors in a stage-dependent manner. We investigated the biological consequence of this RI and demonstrate that its inclusion creates a premature termination codon (PTC), that leads to a 65kDa truncated protein isoform that opposes full-length eIF2Bε to inhibit global translation. Furthermore, expression of 65kDa eIF2Bε led to increased survival of head and neck cancer cells under hypoxia, providing evidence that this isoform enables cells to adapt to conditions of low oxygen. Additional work to uncover -cis and -trans regulators of EIF2B5 splicing identified several factors that influence intron retention in EIF2B5: a weak splicing potential at the RI, hypoxia-induced expression and binding of the splicing factor SRSF3, and increased binding of total and phospho-Ser2 RNA polymerase II specifically at the intron retained under hypoxia. Altogether, these data reveal differential splicing as a previously uncharacterized mode of translational control under hypoxia and are supported by a model in which hypoxia-induced changes to cotranscriptional processing lead to selective retention of a PTC-containing intron in EIF2B5.
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Affiliation(s)
- Lauren K. Brady
- Department of Radiation Oncology Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Cellular and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Hejia Wang
- Department of Biochemistry and Molecular Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Caleb M. Radens
- Cellular and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Yue Bi
- Department of Radiation Oncology Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Oncology Center, Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Milan Radovich
- Indiana University Health Precision Genomics Program, Indianapolis, Indiana, United States of America
- Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, Indiana, United States of America
| | - Amit Maity
- Department of Radiation Oncology Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Cristina Ivan
- Center for RNA Interference and Non-coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Mircea Ivan
- Department of Medicine, Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, Indiana, United States of America
| | - Yoseph Barash
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States of America
- Department of Computer and Information Science, University of Pennsylvania, Philadelphia, United States of America
| | - Constantinos Koumenis
- Department of Radiation Oncology Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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196
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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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197
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Climente-González H, Porta-Pardo E, Godzik A, Eyras E. The Functional Impact of Alternative Splicing in Cancer. Cell Rep 2017; 20:2215-2226. [DOI: 10.1016/j.celrep.2017.08.012] [Citation(s) in RCA: 364] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 07/15/2017] [Accepted: 07/26/2017] [Indexed: 12/29/2022] Open
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198
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Yanagihara T, Tomino T, Uruno T, Fukui Y. Thymic epithelial cell-specific deletion of Jmjd6 reduces Aire protein expression and exacerbates disease development in a mouse model of autoimmune diabetes. Biochem Biophys Res Commun 2017; 489:8-13. [PMID: 28546003 DOI: 10.1016/j.bbrc.2017.05.113] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Accepted: 05/19/2017] [Indexed: 01/09/2023]
Abstract
Thymic epithelial cells (TECs) establish spatially distinct microenvironments in which developing T cells are selected to mature or die. A unique property of medullary TECs is their expression of thousands of tissue-restricted self-antigens that is largely under the control of the transcriptional regulator Aire. We previously showed that Jmjd6, a lysyl hydroxylase for splicing regulatory proteins, is important for Aire protein expression and that transplantation of Jmjd6-deficient thymic stroma into athymic nude mice resulted in multiorgan autoimmunity. Here we report that TEC-specific deletion of Jmjd6 exacerbates development of autoimmune diabetes in a mouse model, which express both ovalbumin (OVA) under the control of the rat insulin gene promoter and OT-I T cell receptor specific for OVA peptide bound to major histocompatibility complex class I Kb molecules. We found that Aire protein expression in mTECs was reduced in the absence of Jmjd6, with retention of intron 2 in Aire transcripts. Our results thus demonstrate the importance of Jmjd6 in establishment of immunological tolerance in a more physiological setting.
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Affiliation(s)
- Toyoshi Yanagihara
- Division of Immunogenetics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan; Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
| | - Takahiro Tomino
- Division of Immunogenetics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takehito Uruno
- Division of Immunogenetics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan; Research Center for Advanced Immunology, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshinori Fukui
- Division of Immunogenetics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan; Research Center for Advanced Immunology, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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199
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Evrony GD, Cordero DR, Shen J, Partlow JN, Yu TW, Rodin RE, Hill RS, Coulter ME, Lam ATN, Jayaraman D, Gerrelli D, Diaz DG, Santos C, Morrison V, Galli A, Tschulena U, Wiemann S, Martel MJ, Spooner B, Ryu SC, Elhosary PC, Richardson JM, Tierney D, Robinson CA, Chibbar R, Diudea D, Folkerth R, Wiebe S, Barkovich AJ, Mochida GH, Irvine J, Lemire EG, Blakley P, Walsh CA. Integrated genome and transcriptome sequencing identifies a noncoding mutation in the genome replication factor DONSON as the cause of microcephaly-micromelia syndrome. Genome Res 2017. [PMID: 28630177 PMCID: PMC5538549 DOI: 10.1101/gr.219899.116] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
While next-generation sequencing has accelerated the discovery of human disease genes, progress has been largely limited to the “low hanging fruit” of mutations with obvious exonic coding or canonical splice site impact. In contrast, the lack of high-throughput, unbiased approaches for functional assessment of most noncoding variants has bottlenecked gene discovery. We report the integration of transcriptome sequencing (RNA-seq), which surveys all mRNAs to reveal functional impacts of variants at the transcription level, into the gene discovery framework for a unique human disease, microcephaly-micromelia syndrome (MMS). MMS is an autosomal recessive condition described thus far in only a single First Nations population and causes intrauterine growth restriction, severe microcephaly, craniofacial anomalies, skeletal dysplasia, and neonatal lethality. Linkage analysis of affected families, including a very large pedigree, identified a single locus on Chromosome 21 linked to the disease (LOD > 9). Comprehensive genome sequencing did not reveal any pathogenic coding or canonical splicing mutations within the linkage region but identified several nonconserved noncoding variants. RNA-seq analysis detected aberrant splicing in DONSON due to one of these noncoding variants, showing a causative role for DONSON disruption in MMS. We show that DONSON is expressed in progenitor cells of embryonic human brain and other proliferating tissues, is co-expressed with components of the DNA replication machinery, and that Donson is essential for early embryonic development in mice as well, suggesting an essential conserved role for DONSON in the cell cycle. Our results demonstrate the utility of integrating transcriptomics into the study of human genetic disease when DNA sequencing alone is not sufficient to reveal the underlying pathogenic mutation.
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Affiliation(s)
- Gilad D Evrony
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Dwight R Cordero
- Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Jun Shen
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.,Laboratory of Molecular Medicine, Partners Personalized Medicine, Cambridge, Massachusetts 02139, USA
| | - Jennifer N Partlow
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Timothy W Yu
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Rachel E Rodin
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - R Sean Hill
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Michael E Coulter
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Anh-Thu N Lam
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Divya Jayaraman
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Dianne Gerrelli
- Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Diana G Diaz
- Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Chloe Santos
- Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Victoria Morrison
- Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Antonella Galli
- Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Ulrich Tschulena
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Stefan Wiemann
- Division of Molecular Genome Analysis, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - M Jocelyne Martel
- Department of Obstetrics and Gynecology, University of Saskatchewan College of Medicine, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Betty Spooner
- Northern Medical Services, University of Saskatchewan College of Medicine, Saskatoon, Saskatchewan S7K 0L4, Canada
| | - Steven C Ryu
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Princess C Elhosary
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Jillian M Richardson
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Danielle Tierney
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
| | - Christopher A Robinson
- Department of Pathology, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - Rajni Chibbar
- Department of Pathology, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - Dana Diudea
- Department of Pathology, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - Rebecca Folkerth
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Sheldon Wiebe
- Department of Medical Imaging, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - A James Barkovich
- Department of Radiology, University of California San Francisco, San Francisco, California 94143, USA
| | - Ganeshwaran H Mochida
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA.,Pediatric Neurology Unit, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - James Irvine
- Northern Medical Services, University of Saskatchewan College of Medicine, Saskatoon, Saskatchewan S7K 0L4, Canada.,Population Health Unit, Mamawetan Churchill River and Keewatin-Yatthé Health Regions, and Athabasca Health Authority, La Ronge, Saskatchewan S0J 1L0, Canada
| | - Edmond G Lemire
- Department of Pediatrics, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - Patricia Blakley
- Department of Pediatrics, Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan S7N 0W8, Canada
| | - Christopher A Walsh
- Division of Genetics and Genomics, Manton Center for Orphan Disease, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Departments of Neurology and Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA
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200
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Wang J, Dumartin L, Mafficini A, Ulug P, Sangaralingam A, Alamiry NA, Radon TP, Salvia R, Lawlor RT, Lemoine NR, Scarpa A, Chelala C, Crnogorac-Jurcevic T. Splice variants as novel targets in pancreatic ductal adenocarcinoma. Sci Rep 2017; 7:2980. [PMID: 28592875 PMCID: PMC5462735 DOI: 10.1038/s41598-017-03354-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 04/26/2017] [Indexed: 12/22/2022] Open
Abstract
Despite a wealth of genomic information, a comprehensive alternative splicing (AS) analysis of pancreatic ductal adenocarcinoma (PDAC) has not been performed yet. In the present study, we assessed whole exome-based transcriptome and AS profiles of 43 pancreas tissues using Affymetrix exon array. The AS analysis of PDAC indicated on average two AS probe-sets (ranging from 1-28) in 1,354 significantly identified protein-coding genes, with skipped exon and alternative first exon being the most frequently utilised. In addition to overrepresented extracellular matrix (ECM)-receptor interaction and focal adhesion that were also seen in transcriptome differential expression (DE) analysis, Fc gamma receptor-mediated phagocytosis and axon guidance AS genes were also highly represented. Of note, the highest numbers of AS probe-sets were found in collagen genes, which encode the characteristically abundant stroma seen in PDAC. We also describe a set of 37 'hypersensitive' genes which were frequently targeted by somatic mutations, copy number alterations, DE and AS, indicating their propensity for multidimensional regulation. We provide the most comprehensive overview of the AS landscape in PDAC with underlying changes in the spliceosomal machinery. We also collate a set of AS and DE genes encoding cell surface proteins, which present promising diagnostic and therapeutic targets in PDAC.
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Affiliation(s)
- Jun Wang
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK.
| | - Laurent Dumartin
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Andrea Mafficini
- ARC-Net Research Centre and Department of Diagnostics and Publich Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
| | - Pinar Ulug
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Ajanthah Sangaralingam
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Namaa Audi Alamiry
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Tomasz P Radon
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Roberto Salvia
- ARC-Net Research Centre and Department of Diagnostics and Publich Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
| | - Rita T Lawlor
- ARC-Net Research Centre and Department of Diagnostics and Publich Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
| | - Nicholas R Lemoine
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Aldo Scarpa
- ARC-Net Research Centre and Department of Diagnostics and Publich Health, Section of Pathology, University and Hospital Trust of Verona, Verona, Italy
| | - Claude Chelala
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Tatjana Crnogorac-Jurcevic
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK.
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