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Rahn K, Abdallah AT, Gan L, Herbrich S, Sonntag R, Benitez O, Malaney P, Zhang X, Rodriguez AG, Brottem J, Marx G, Brümmendorf TH, Ostareck DH, Ostareck-Lederer A, Crysandt M, Post SM, Naarmann-de Vries IS. Insight into the mechanism of AML del(9q) progression: hnRNP K targets the myeloid master regulators CEBPA (C/EBPα) and SPI1 (PU.1). BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195004. [PMID: 38008244 DOI: 10.1016/j.bbagrm.2023.195004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 11/08/2023] [Accepted: 11/20/2023] [Indexed: 11/28/2023]
Abstract
Deletions on the long arm of chromosome 9 (del(9q)) are recurrent abnormalities in about 2 % of acute myeloid leukemia cases, which usually involve HNRNPK and are frequently associated with other known aberrations. Based on an Hnrnpk haploinsufficient mouse model, a recent study demonstrated a function of hnRNP K in pathogenesis of myeloid malignancies via the regulation of cellular proliferation and myeloid differentiation programs. Here, we provide evidence that reduced hnRNP K expression results in the dysregulated expression of C/EBPα and additional transcription factors. CyTOF analysis revealed monocytic skewing with increased levels of mature myeloid cells. To explore the role of hnRNP K during normal and pathological myeloid differentiation in humans, we characterized hnRNP K-interacting RNAs in human AML cell lines. Notably, RNA-sequencing revealed several mRNAs encoding key transcription factors involved in the regulation of myeloid differentiation as targets of hnRNP K. We showed that specific sequence motifs confer the interaction of SPI1 and CEBPA 5' and 3'UTRs with hnRNP K. The siRNA mediated reduction of hnRNP K in human AML cells resulted in an increase of PU.1 and C/EBPα that is most pronounced for the p30 isoform. The combinatorial treatment with the inducer of myeloid differentiation valproic acid resulted in increased C/EBPα expression and myeloid differentiation. Together, our results indicate that hnRNP K post-transcriptionally regulates the expression of myeloid master transcription factors. These novel findings can inaugurate novel options for targeted treatment of AML del(9q) by modulation of hnRNP K function.
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Affiliation(s)
- Kerstin Rahn
- Department of Intensive Care Medicine, University Hospital RWTH Aachen University, Aachen, Germany; Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ali T Abdallah
- Interdisciplinary Center for Clinical Research (IZKF) Aachen, RWTH Aachen University, Germany; Cluster of Excellence on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Lin Gan
- Interdisciplinary Center for Clinical Research (IZKF) Aachen, RWTH Aachen University, Germany
| | - Shelley Herbrich
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Roland Sonntag
- Department of Internal Medicine III, University Hospital RWTH Aachen University, Aachen, Germany
| | - Oscar Benitez
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Prerna Malaney
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Xiaorui Zhang
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ashely G Rodriguez
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jared Brottem
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Gernot Marx
- Department of Intensive Care Medicine, University Hospital RWTH Aachen University, Aachen, Germany
| | - Tim H Brümmendorf
- Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation, University Hospital RWTH Aachen University, Aachen, Germany; Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), Aachen, Germany
| | - Dirk H Ostareck
- Department of Intensive Care Medicine, University Hospital RWTH Aachen University, Aachen, Germany
| | - Antje Ostareck-Lederer
- Department of Intensive Care Medicine, University Hospital RWTH Aachen University, Aachen, Germany
| | - Martina Crysandt
- Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation, University Hospital RWTH Aachen University, Aachen, Germany; Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), Aachen, Germany
| | - Sean M Post
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - Isabel S Naarmann-de Vries
- Department of Intensive Care Medicine, University Hospital RWTH Aachen University, Aachen, Germany; Section of Bioinformatics and Systems Cardiology, University Hospital Heidelberg, Heidelberg, Germany.
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Li B, Yao B, Guo X, Wang Z, Xie W, Wu X, Wang F, Mei Y. c-Myc-induced long noncoding RNA MIRE cooperates with hnRNPK to stabilize ELF2 mRNA and promotes clear cell renal cell carcinogenesis. Cancer Gene Ther 2023; 30:1215-1226. [PMID: 37248433 DOI: 10.1038/s41417-023-00631-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 05/31/2023]
Abstract
Elevated expression of c-Myc is associated with a variety of human cancers including clear cell renal cell carcinoma (ccRCC). Increasing evidence suggests that long noncoding RNAs (lncRNAs) are an important class of molecules that regulate both tumor initiation and progression. Here, we report the lncRNA c-Myc-induced regulator of ELF2 (MIRE) as a transcriptional target of c-Myc. MIRE functions as an oncogenic molecule in ccRCC by increasing ELF2 expression. Mechanistically, MIRE promotes phase separation of the RNA binding protein hnRNPK and facilitates the binding of hnRNPK to ELF2 mRNA, thereby resulting in the stabilization of ELF2 mRNA. Interestingly, MIRE is also under transcriptional control by ELF2, establishing an ELF2-MIRE positive feedback loop. Together, these findings provide new insights into the mechanisms by which c-Myc promotes tumorigenesis. They also implicate MIRE as an important regulator of ccRCC carcinogenesis.
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Affiliation(s)
- Bingyan Li
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Bo Yao
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Xiaorui Guo
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Zhongyu Wang
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Wei Xie
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China
- DeepBio Technology Ltd Co., 515 ShenNan Road, Shanghai, 201612, China
| | - Xianning Wu
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
| | - Fang Wang
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
| | - Yide Mei
- The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at Microscale, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.
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3
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Hung SH, Elliott GI, Ramkumar TR, Burtnyak L, McGrenaghan CJ, Alkuzweny S, Quaiyum S, Iwata-Reuyl D, Pan X, Green BD, Kelly VP, de Crécy-Lagard V, Swairjo M. Structural basis of Qng1-mediated salvage of the micronutrient queuine from queuosine-5'-monophosphate as the biological substrate. Nucleic Acids Res 2023; 51:935-951. [PMID: 36610787 PMCID: PMC9881137 DOI: 10.1093/nar/gkac1231] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 12/02/2022] [Accepted: 12/10/2022] [Indexed: 01/09/2023] Open
Abstract
Eukaryotic life benefits from-and ofttimes critically relies upon-the de novo biosynthesis and supply of vitamins and micronutrients from bacteria. The micronutrient queuosine (Q), derived from diet and/or the gut microbiome, is used as a source of the nucleobase queuine, which once incorporated into the anticodon of tRNA contributes to translational efficiency and accuracy. Here, we report high-resolution, substrate-bound crystal structures of the Sphaerobacter thermophilus queuine salvage protein Qng1 (formerly DUF2419) and of its human ortholog QNG1 (C9orf64), which together with biochemical and genetic evidence demonstrate its function as the hydrolase releasing queuine from queuosine-5'-monophosphate as the biological substrate. We also show that QNG1 is highly expressed in the liver, with implications for Q salvage and recycling. The essential role of this family of hydrolases in supplying queuine in eukaryotes places it at the nexus of numerous (patho)physiological processes associated with queuine deficiency, including altered metabolism, proliferation, differentiation and cancer progression.
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Affiliation(s)
- Shr-Hau Hung
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, USA
- The Viral Information Institute, San Diego State University, San Diego, CA, USA
| | - Gregory I Elliott
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, USA
| | - Thakku R Ramkumar
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Lyubomyr Burtnyak
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Callum J McGrenaghan
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Sana Alkuzweny
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, USA
| | - Samia Quaiyum
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Dirk Iwata-Reuyl
- Department of Chemistry, PO Box 751 Portland State University, Portland, OR 97207, USA
| | - Xiaobei Pan
- School of Biological Sciences, Institute for Global Food Security, Queen's University Belfast, Belfast, UK
| | - Brian D Green
- School of Biological Sciences, Institute for Global Food Security, Queen's University Belfast, Belfast, UK
| | - Vincent P Kelly
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
- University of Florida Genetics Institute, Gainesville, FL 32610, USA
| | - Manal A Swairjo
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, CA, USA
- The Viral Information Institute, San Diego State University, San Diego, CA, USA
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The Role of RNA-Binding Proteins in Hematological Malignancies. Int J Mol Sci 2022; 23:ijms23179552. [PMID: 36076951 PMCID: PMC9455611 DOI: 10.3390/ijms23179552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/18/2022] [Accepted: 08/21/2022] [Indexed: 11/17/2022] Open
Abstract
Hematological malignancies comprise a plethora of different neoplasms, such as leukemia, lymphoma, and myeloma, plus a myriad of dysplasia, such as myelodysplastic syndromes or anemias. Despite all the advances in patient care and the development of new therapies, some of these malignancies remain incurable, mainly due to resistance and refractoriness to treatment. Therefore, there is an unmet clinical need to identify new biomarkers and potential therapeutic targets that play a role in treatment resistance and contribute to the poor outcomes of these tumors. RNA-binding proteins (RBPs) are a diverse class of proteins that interact with transcripts and noncoding RNAs and are involved in every step of the post-transcriptional processing of transcripts. Dysregulation of RBPs has been associated with the development of hematological malignancies, making them potential valuable biomarkers and potential therapeutic targets. Although a number of dysregulated RBPs have been identified in hematological malignancies, there is a critical need to understand the biology underlying their contribution to pathology, such as the spatiotemporal context and molecular mechanisms involved. In this review, we emphasize the importance of deciphering the regulatory mechanisms of RBPs to pinpoint novel therapeutic targets that could drive or contribute to hematological malignancy biology.
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Genome-Wide Association Study Identifies Multiple Susceptibility Loci for Malignant Neoplasms of the Brain in Taiwan. J Pers Med 2022; 12:jpm12071161. [PMID: 35887658 PMCID: PMC9323978 DOI: 10.3390/jpm12071161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/04/2022] [Accepted: 07/14/2022] [Indexed: 11/22/2022] Open
Abstract
Primary brain malignancy is a rare tumor with a global incidence of less than 10 per 100,000 people. Hence, there is limited power for identifying risk loci in individual studies, especially for Han Chinese. We performed a genome-wide association study (GWAS) in Taiwan, including 195 cases and 195 controls. We identified five new genes for malignant neoplasms of the brain: EDARADD (rs645507, 1p31.3, p = 7.71 × 10−5, odds ratio (OR) = 1.893), RBFOX1 (rs8044700, p = 2.35 × 10−5, OR = 2.36), LMF1 (rs3751667, p = 7.24 × 10−7, OR = 2.17), DPP6 (rs67433368, p = 8.32 × 10−5, OR = 3.94), and NDUFB9 (rs7827791, p = 9.73 × 10−6, OR = 4.42). These data support that genetic susceptibility toward GBM or non-GBM tumors is highly distinct, likely reflecting different etiologies. Combined with signaling analysis, we found that RNA modification may be related to major risk factors in primary malignant neoplasms of the brain.
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Shin TH, Theodorou E, Holland C, Yamin R, Raggio CL, Giampietro PF, Sweetser DA. TLE4 Is a Critical Mediator of Osteoblast and Runx2-Dependent Bone Development. Front Cell Dev Biol 2021; 9:671029. [PMID: 34422801 PMCID: PMC8377417 DOI: 10.3389/fcell.2021.671029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 07/14/2021] [Indexed: 11/13/2022] Open
Abstract
Healthy bone homeostasis hinges upon a delicate balance and regulation of multiple processes that contribute to bone development and metabolism. While examining hematopoietic regulation by Tle4, we have uncovered a previously unappreciated role of Tle4 on bone calcification using a novel Tle4 null mouse model. Given the significance of osteoblasts in both hematopoiesis and bone development, this study investigated how loss of Tle4 affects osteoblast function. We used dynamic bone formation parameters and microCT to characterize the adverse effects of Tle4 loss on bone development. We further demonstrated loss of Tle4 impacts expression of several key osteoblastogenic genes, including Runx2, Oc, and Ap, pointing toward a potential novel mechanism for Tle4-dependent regulation of mammalian bone development in collaboration with the RUNX family members.
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Affiliation(s)
- Thomas H. Shin
- Department of Pediatrics, Center of Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
- Department of Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA, United States
| | - Evangelos Theodorou
- Department of Pediatrics, Center of Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Carl Holland
- Department of Pediatrics, Center of Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Rae’e Yamin
- Department of Pediatrics, Center of Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Cathleen L. Raggio
- Department of Pediatric Orthopedics, Hospital for Special Surgery, New York, NY, United States
| | | | - David A. Sweetser
- Department of Pediatrics, Center of Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
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7
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Large Rab GTPases: Novel Membrane Trafficking Regulators with a Calcium Sensor and Functional Domains. Int J Mol Sci 2021; 22:ijms22147691. [PMID: 34299309 PMCID: PMC8303950 DOI: 10.3390/ijms22147691] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 12/28/2022] Open
Abstract
Rab GTPases are major coordinators of intracellular membrane trafficking, including vesicle transport, membrane fission, tethering, docking, and fusion events. Rab GTPases are roughly divided into two groups: conventional “small” Rab GTPases and atypical “large” Rab GTPases that have been recently reported. Some members of large Rab GTPases in mammals include Rab44, Rab45/RASEF, and Rab46. The genes of these large Rab GTPases commonly encode an amino-terminal EF-hand domain, coiled-coil domain, and the carboxyl-terminal Rab GTPase domain. A common feature of large Rab GTPases is that they express several isoforms in cells. For instance, Rab44’s two isoforms have similar functions, but exhibit differential localization. The long form of Rab45 (Rab45-L) is abundantly distributed in epithelial cells. The short form of Rab45 (Rab45-S) is predominantly present in the testes. Both Rab46 (CRACR2A-L) and the short isoform lacking the Rab domain (CRACR2A-S) are expressed in T cells, whereas Rab46 is only distributed in endothelial cells. Although evidence regarding the function of large Rab GTPases has been accumulating recently, there are only a limited number of studies. Here, we report the recent findings on the large Rab GTPase family concerning their function in membrane trafficking, cell differentiation, related diseases, and knockout mouse phenotypes.
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8
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Aref S, El-Ghonemy MS, Atia DM, Elbaiomy MM, Abdelsalam SA, Tawfik A, El-Sebaie A. Prognostic Value of TLE1 Gene Expression in Patients with T-cell Acute Lymphoblastic Leukemia. Asian Pac J Cancer Prev 2021; 22:1653-1658. [PMID: 34048198 PMCID: PMC8408389 DOI: 10.31557/apjcp.2021.22.5.1653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Indexed: 11/25/2022] Open
Abstract
Background: Transducin-like enhancer of split 1 (TLE1( is a member of the TLE family of transcriptional co-repressors that control the transcription of a wide range of genes. The aim of this study was to evaluate the prognostic role of TLE1 gene expression in patients with T-cell acute lymphoblastic leukemia (T-ALL). Method: This study was conducted on 97 newly diagnosed T-ALL patients admitted to the Mansoura University oncology center (59 males and 38 females) with median age (33 years) in addition to 102 apparently healthy individuals served as a control group. TLE1 gene expression was measured in both patients and control groups by real time – PCR. The calculation of relative gene expression was done using the ΔΔCt method. Results: TEL1 gene expression was significantly down regulated in T-ALL cases (median 2.83) as compared to controls (median 84.65) (p < 0.001). The low TEL1 gene expression was significantly associated with CNS infiltration, non-remission and higher relapse rate (p< 0.001, 0.001 and 0.023 respectively). Likewise, Low TEL1 gene expression was significantly associated with shorter OS and DFS (P= 0.012 and 0.011 respectively). Furthermore, Low TEL1 gene expression was considered as risk predictor of relapse with OR 3.636(CI.1.422-9.295) (P =0.007); and OR 0.803(CI. 0.609-0.96) (P=0.021) and independent predictor of T-ALL patient’s outcome with OR 0.619 (CI. 0.44-0.872) (P=0.006). Conclusion: TLE1 gene expression was significantly down regulated in T-ALL cases as compared with controls. Low TLE1 expression is independent predictor of the T-ALL patient’s outcome.
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Affiliation(s)
- Salah Aref
- Hematology Unit, Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed Sabry El-Ghonemy
- Hematology Unit, Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Doaa Mohamed Atia
- Hematology Unit, Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mohamed M Elbaiomy
- Medical Oncology Unit, Mansoura University Oncology Center; Mansoura; Egypt
| | | | - Aya Tawfik
- Clinical pharmacy, Faculty of pharmacy, Mansoura University, Egypt
| | - Ahmed El-Sebaie
- Hematology Unit, Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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Cerasuolo A, Buonaguro L, Buonaguro FM, Tornesello ML. The Role of RNA Splicing Factors in Cancer: Regulation of Viral and Human Gene Expression in Human Papillomavirus-Related Cervical Cancer. Front Cell Dev Biol 2020; 8:474. [PMID: 32596243 PMCID: PMC7303290 DOI: 10.3389/fcell.2020.00474] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/20/2020] [Indexed: 12/12/2022] Open
Abstract
The spliceosomal complex components, together with the heterogeneous nuclear ribonucleoproteins (hnRNPs) and serine/arginine-rich (SR) proteins, regulate the process of constitutive and alternative splicing, the latter leading to the production of mRNA isoforms coding multiple proteins from a single pre-mRNA molecule. The expression of splicing factors is frequently deregulated in different cancer types causing the generation of oncogenic proteins involved in cancer hallmarks. Cervical cancer is caused by persistent infection with oncogenic human papillomaviruses (HPVs) and constitutive expression of viral oncogenes. The aberrant activity of hnRNPs and SR proteins in cervical neoplasia has been shown to trigger the production of oncoproteins through the processing of pre-mRNA transcripts either derived from human genes or HPV genomes. Indeed, hnRNP and SR splicing factors have been shown to regulate the production of viral oncoprotein isoforms necessary for the completion of viral life cycle and for cell transformation. Target-therapy strategies against hnRNPs and SR proteins, causing simultaneous reduction of oncogenic factors and inhibition of HPV replication, are under development. In this review, we describe the current knowledge of the functional link between RNA splicing factors and deregulated cellular as well as viral RNA maturation in cervical cancer and the opportunity of new therapeutic strategies.
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Affiliation(s)
| | | | | | - Maria Lina Tornesello
- Molecular Biology and Viral Oncology Unit, Istituto Nazionale Tumouri IRCCS–Fondazione G. Pascale, Naples, Italy
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Mohibi S, Chen X, Zhang J. Cancer the'RBP'eutics-RNA-binding proteins as therapeutic targets for cancer. Pharmacol Ther 2019; 203:107390. [PMID: 31302171 DOI: 10.1016/j.pharmthera.2019.07.001] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/02/2019] [Indexed: 12/11/2022]
Abstract
RNA-binding proteins (RBPs) play a critical role in the regulation of various RNA processes, including splicing, cleavage and polyadenylation, transport, translation and degradation of coding RNAs, non-coding RNAs and microRNAs. Recent studies indicate that RBPs not only play an instrumental role in normal cellular processes but have also emerged as major players in the development and spread of cancer. Herein, we review the current knowledge about RNA binding proteins and their role in tumorigenesis as well as the potential to target RBPs for cancer therapeutics.
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Affiliation(s)
- Shakur Mohibi
- Comparative Oncology Laboratory, Schools of Veterinary Medicine and Medicine, University of California at Davis, United States
| | - Xinbin Chen
- Comparative Oncology Laboratory, Schools of Veterinary Medicine and Medicine, University of California at Davis, United States
| | - Jin Zhang
- Comparative Oncology Laboratory, Schools of Veterinary Medicine and Medicine, University of California at Davis, United States.
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11
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Characterization of acute myeloid leukemia with del(9q) - Impact of the genes in the minimally deleted region. Leuk Res 2018; 76:15-23. [PMID: 30476680 DOI: 10.1016/j.leukres.2018.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/13/2018] [Accepted: 11/15/2018] [Indexed: 02/06/2023]
Abstract
Acute myeloid leukemia is an aggressive disease that arises from clonal expansion of malignant hematopoietic precursor cells of the bone marrow. Deletions on the long arm of chromosome 9 (del(9q)) are observed in 2% of acute myeloid leukemia patients. Our deletion analysis in a cohort of 31 del(9q) acute myeloid leukemia patients further supports the importance of a minimally deleted region composed of seven genes potentially involved in leukemogenesis: GKAP1, KIF27, C9ORF64, HNRNPK, RMI1, SLC28A3 and NTRK2. Importantly, among them HNRNPK, encoding heterogeneous nuclear ribonucleoprotein K is proposed to function in leukemogenesis. We show that expression of HNRNPK and the other genes of the minimally deleted region is significantly reduced in patients with del(9q) compared with normal karyotype acute myeloid leukemia. Also, two mRNAs interacting with heterogeneous nuclear ribonucleoprotein K, namely CDKN1A and CEBPA are significantly downregulated. While the deletion size is not correlated with outcome, associated genetic aberrations are important. Patients with an additional t(8;21) show a good prognosis. RUNX1-RUNX1T1, which emerges from the t(8;21) leads to transcriptional down-regulation of CEBPA. Acute myeloid leukemia patients with mutations in CEBPA have a good prognosis as well. Interestingly, in del(9q) patients with CEBPA mutation mRNA levels of HNRNPK and the other genes located in the minimally deleted region is restored to normal karyotype level. Our data indicate that a link between CEBPA and the genes of the minimally deleted region, among them HNRNPK contributes to leukemogenesis in acute myeloid leukemia with del(9q).
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12
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RASEF expression correlates with hormone receptor status in breast cancer. Oncol Lett 2018; 16:7223-7230. [PMID: 30546460 DOI: 10.3892/ol.2018.9542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 09/25/2018] [Indexed: 12/14/2022] Open
Abstract
Breast cancer (BC) is the most frequently diagnosed malignant tumor in women worldwide, and the development of new molecules associated with BC is essential for the management of this disease. RAS and EF-hand domain-containing (RASEF) encodes the GTPase enzyme that belongs to the Rab family. Although the effects of this gene have been reported in several malignant tumor types, the role of RASEF in BC has not been completely elucidated. The aim of the present study was to investigate the importance of RASEF expression in BC. RASEF mRNA expression levels were evaluated in BC and non-cancerous mammary cell lines. The association between RASEF mRNA expression levels and clinicopathological factors in 167 patients with BC were then determined. Among the 13 examined BC cell lines, ER-negative/HER2-negative cell lines expressed lower RASEF mRNA levels, when compared with the other examined cell lines (P=0.014). Of the 167 patients examined, patients with negative hormone receptor status exhibited significantly lower RASEF mRNA expression levels (P<0.001). In addition low RASEF expression in BC tissues was associated with negative estrogen receptor status (P<0.001), negative progesterone receptor status (P<0.001), and triple-negative status (P<0.001). Additionally, although the differences were not statistically significant, patients with low RASEF expression levels exhibited poorer disease-free survival (P=0.123) and overall survival (P=0.086) than other patients. The results of the present study indicate that RASEF mRNA expression levels are associated with hormone receptor status in BC.
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13
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Brassesco MS, Pezuk JA, Cortez MA, Bezerra Salomão K, Scrideli CA, Tone LG. TLE1 as an indicator of adverse prognosis in pediatric acute lymphoblastic leukemia. Leuk Res 2018; 74:42-46. [PMID: 30286331 DOI: 10.1016/j.leukres.2018.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 06/27/2018] [Accepted: 09/22/2018] [Indexed: 11/28/2022]
Abstract
PURPOSE Acute lymphoblastic leukemia (ALL) is the most common type of cancer in children, and despite the high rate of cure (over 80%) it still has a big impact on morbidity and mortality. The Transducin-like enhancer of split 1 (TLE1), a transcriptional corepressor, has been described as dysregulated and recently emerged as a tumor marker in several cancer types, including hematologic malignancies. METHODS In the present study TLE1 gene expression was evaluated by RT-qPCR. A total of 60 consecutive pathological ALL samples and 8 normal bone marrow samples were included. Associations between TLE1 levels and clinicopathological features were estimated using Mann-Whitney tests. RESULTS TLE1 mRNA levels were significantly diminished in ALL samples when compared to normal counterparts (fold change -1.45, p-value 0.039). Lower TLE1 expression levels were associated with poorer prognostic features such as age at diagnosis (<1 or >9 years-old), absence of the Common Acute Lymphoblastic Leukemia Antigen (CALLA) and high white cell count. Considering immunophenotype, decreased expression of TLE1 was only evident for T-cell ALL, what was validated using gene expression profiling data available in public repositories. No associations with event or overall survival were observed. However, TLE1 expression was statistically different between patients who achieved complete clinical remission (CCR) from those that relapsed or died. CONCLUSION These data are of particular interest and give support for a plausible role of TLE1 as a tumor suppressor in T-cell ALL. Moreover, the prognostic value of this corepressor may assist ALL treatment stratification and suggest the need of alternative regimens.
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Affiliation(s)
- María Sol Brassesco
- Department of Biology, Faculty of Philosophy, Sciences and Letters at Ribeirao Preto, Brazil.
| | - Julia Alejandra Pezuk
- Department of Pharmacy and Department of Biotechnology and Health Innovation, Anhanguera University of Sao Paulo, UNIAN/SP, Brazil
| | - Maria Angelica Cortez
- Experimental Radiation Oncology, The University of Texas, MD Anderson Cancer Center, USA
| | - Karina Bezerra Salomão
- Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Brazil
| | | | - Luiz Gonzaga Tone
- Department of Pediatrics, Ribeirao Preto Medical School, University of Sao Paulo, Brazil
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14
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Urbanski L, Leclair N, Anczuków O. Alternative-splicing defects in cancer: Splicing regulators and their downstream targets, guiding the way to novel cancer therapeutics. WILEY INTERDISCIPLINARY REVIEWS. RNA 2018; 9:e1476. [PMID: 29693319 PMCID: PMC6002934 DOI: 10.1002/wrna.1476] [Citation(s) in RCA: 205] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/27/2018] [Accepted: 03/01/2018] [Indexed: 12/14/2022]
Abstract
Defects in alternative splicing are frequently found in human tumors and result either from mutations in splicing-regulatory elements of specific cancer genes or from changes in the regulatory splicing machinery. RNA splicing regulators have emerged as a new class of oncoproteins and tumor suppressors, and contribute to disease progression by modulating RNA isoforms involved in the hallmark cancer pathways. Thus, dysregulation of alternative RNA splicing is fundamental to cancer and provides a potentially rich source of novel therapeutic targets. Here, we review the alterations in splicing regulatory factors detected in human tumors, as well as the resulting alternatively spliced isoforms that impact cancer hallmarks, and discuss how they contribute to disease pathogenesis. RNA splicing is a highly regulated process and, as such, the regulators are themselves tightly regulated. Differential transcriptional and posttranscriptional regulation of splicing factors modulates their levels and activities in tumor cells. Furthermore, the composition of the tumor microenvironment can also influence which isoforms are expressed in a given cell type and impact drug responses. Finally, we summarize current efforts in targeting alternative splicing, including global splicing inhibition using small molecules blocking the spliceosome or splicing-factor-modifying enzymes, as well as splice-switching RNA-based therapeutics to modulate cancer-specific splicing isoforms. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > Splicing Regulation/Alternative Splicing.
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15
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SNP-array lesions in core binding factor acute myeloid leukemia. Oncotarget 2018; 9:6478-6489. [PMID: 29464086 PMCID: PMC5814226 DOI: 10.18632/oncotarget.24031] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 01/03/2018] [Indexed: 01/09/2023] Open
Abstract
Acute myeloid leukemia (AML) with t(8;21) and inv(16), together referred as core binding factor (CBF)-AML, are recognized as unique entities. Both rearrangements share a common pathophysiology, the disruption of the CBF, and a relatively good prognosis. Experiments have demonstrated that CBF rearrangements were insufficient to induce leukemia, implying the existence of cooperating events. To explore these aberrations, we performed single nucleotide polymorphism (SNP)-array in a well-annotated cohort of 198 patients with CBF-AML. Excluding breakpoint-associated lesions, the most frequent events included loss of a sex chromosome (53%), deletions at 9q21 (12%) and 7q36 (9%) in patients with t(8;21) compared with trisomy 22 (13%), trisomy 8 (10%) and 7q36 deletions (12%) in patients with inv(16). SNP-array revealed novel recurrent genetic alterations likely to be involved in CBF-AML leukemogenesis. ZBTB7A mutations (20% of t(8;21)-AML) were shown to be a target of copy-neutral losses of heterozygosity (CN-LOH) at chromosome 19p. FOXP1 focal deletions were identified in 5% of inv(16)-AML while sequence analysis revealed that 2% carried FOXP1 truncating mutations. Finally, CCDC26 disruption was found in both subtypes (4.5% of the whole cohort) and possibly highlighted a new lesion associated with aberrant tyrosine kinase signaling in this particular subtype of leukemia.
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16
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Gallardo M, Hornbaker MJ, Zhang X, Hu P, Bueso-Ramos C, Post SM. Aberrant hnRNP K expression: All roads lead to cancer. Cell Cycle 2017; 15:1552-7. [PMID: 27049467 DOI: 10.1080/15384101.2016.1164372] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The classification of a gene as an oncogene or a tumor suppressor has been a staple of cancer biology for decades. However, as we delve deeper into the biology of these genes, this simple classification has become increasingly difficult for some. In the case of heterogeneous nuclear ribonuclear protein K (hnRNP K), its role as a tumor suppressor has recently been described in acute myeloid leukemia and demonstrated in a haploinsufficient mouse model. In contrast, data from other clinical correlation studies suggest that hnRNP K may be more fittingly described as an oncogene, due to its increased levels in a variety of malignancies. hnRNP K is a multifunctional protein that can regulate both oncogenic and tumor suppressive pathways through a bevy of chromatin-, DNA-, RNA-, and protein-mediated activates, suggesting its aberrant expression may have broad-reaching cellular impacts. In this review, we highlight our current understanding of hnRNP K, with particular emphasis on its apparently dichotomous roles in tumorigenesis.
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Affiliation(s)
- Miguel Gallardo
- a Department of Leukemia , The University of Texas, MD Anderson Cancer Center , Houston , TX , USA
| | - Marisa J Hornbaker
- a Department of Leukemia , The University of Texas, MD Anderson Cancer Center , Houston , TX , USA.,b The University of Texas Graduate School of Biomedical Sciences at Houston , Houston , TX , USA
| | - Xiaorui Zhang
- a Department of Leukemia , The University of Texas, MD Anderson Cancer Center , Houston , TX , USA
| | - Peter Hu
- c School of Health Professions, The University of Texas, MD Anderson Cancer Center , Houston , TX , USA
| | - Carlos Bueso-Ramos
- d Department of Hematopathology , The University of Texas, MD Anderson Cancer Center , Houston , TX , USA
| | - Sean M Post
- a Department of Leukemia , The University of Texas, MD Anderson Cancer Center , Houston , TX , USA
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17
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Abstract
More than 60 Rab GTPases exist in the human genome to regulate vesicle trafficking between organelles. Rab GTPases are members of the Ras GTPase superfamily that broadly control budding, uncoating, motility and fusion of vesicles in most cell types. Rab proteins interconvert between active, GTP-bound form and inactive, GDP-bound form. In their active conformation, they interact with various effector molecules to carry out diverse functions. Rab GTPases are usually small containing only a GTPase domain with a C-terminal prenylation site for membrane anchoring. Recently, we identified a large G protein, CRACR2A (CRAC channel regulator 2A), which uncovers novel functions of Rab GTPases. First, CRACR2A encodes a large Rab GTPase containing multiple functional domains contrary to small Rab GTPases. Second, CRACR2A plays an unexpected role in regulating intracellular signaling pathways important for T cell activation, unlike the canonical role of small Rab GTPases. Vesicles containing CRACR2A bud out from the proximal Golgi area and translocate into the immunological synapse to activate these signaling pathways. Third, instead of recycling, CRACR2A is consumed by a unidirectional pathway. These events are sequentially regulated by prenylation, GTP binding, protein interaction with a signaling adaptor Vav1, and degradation. Together, our findings reveal a novel function of a large Rab GTPase in intracellular signaling pathways, which may be shared by other large Rab GTPases, Rab44 and Rab45.
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Affiliation(s)
- Sonal Srikanth
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
| | - Jin Seok Woo
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
| | - Yousang Gwack
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
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18
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Li Y, Jia R, Ge S. Role of Epigenetics in Uveal Melanoma. Int J Biol Sci 2017; 13:426-433. [PMID: 28529451 PMCID: PMC5436563 DOI: 10.7150/ijbs.18331] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 01/04/2017] [Indexed: 01/02/2023] Open
Abstract
Uveal melanoma (UM) is a severe human malignancy with a high mortality rate that demands continued research into new and alternative forms of prevention and treatment. The emerging field of epigenetics is beginning to unfold an era of contemporary approaches to reducing the risk and improving the clinical treatment of UM. Epigenetic changes have a high prevalence rate in cancer, are reversible in nature, and can lead to cancer characteristics even in mutation-free cells. The information contained in this review highlights and expands on the main mechanisms of epigenetic dysregulation in UM tumorigenesis, progression and metastasis, including microRNA expression, hypermethylation of genes and histone modification. Epigenetic drugs have been shown to enhance tumor suppressor gene expression and drug sensitivity in many other cancer cell lines and animal models. An increased understanding of epigenetic mechanisms in UM will be invaluable in the design of more potent epigenetic drugs, which when used in combination with traditional therapies, may permit improved therapeutic outcomes.
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Affiliation(s)
| | - Renbing Jia
- ✉ Corresponding authors: Shengfang Ge or Renbing Jia. or
| | - Shengfang Ge
- ✉ Corresponding authors: Shengfang Ge or Renbing Jia. or
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19
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Herold T, Metzeler KH, Vosberg S, Hartmann L, Jurinovic V, Opatz S, Konstandin NP, Schneider S, Zellmeier E, Ksienzyk B, Graf A, Krebs S, Blum H, Cristina Sauerland M, Büchner T, Berdel WE, Wörmann BJ, Mansmann U, Hiddemann W, Bohlander SK, Spiekermann K, Greif PA. Acute myeloid leukemia with del(9q) is characterized by frequent mutations of NPM1, DNMT3A, WT1 and low expression of TLE4. Genes Chromosomes Cancer 2016; 56:75-86. [PMID: 27636548 DOI: 10.1002/gcc.22418] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/26/2016] [Accepted: 08/27/2016] [Indexed: 12/17/2022] Open
Abstract
Deletions of the long arm of chromosome 9 [del(9q)] are a rare but recurring aberration in acute myeloid leukemia (AML). Del(9q) can be found as the sole abnormality or in combination with other cytogenetic aberrations such as t(8;21) and t(15;17). TLE1 and TLE4 were identified to be critical genes contained in the 9q region. We performed whole exome sequencing of 5 patients with del(9q) as the sole abnormality followed by targeted amplicon sequencing of 137 genes of 26 patients with del(9q) as sole or combined with other aberrations. We detected frequent mutations in NPM1 (10/26; 38%), DNMT3A (8/26; 31%), and WT1 (8/26; 31%) but only few FLT3-ITDs (2/26; 8%). All mutations affecting NPM1 and DNMT3A were exclusively identified in patients with del(9q) as the sole abnormality and were significantly more frequent compared to 111 patients classified as intermediate-II according to the European LeukemiaNet (10/14, 71% vs. 22/111, 20%; P < 0.001, 8/14, 57% vs. 26/111, 23%; P = 0.02). Furthermore, we identified DNMT3B to be rarely but recurrently targeted by truncating mutations in AML. Gene expression analysis of 13 patients with del(9q) and 454 patients with normal karyotype or various cytogenetic aberrations showed significant down regulation of TLE4 in patients with del(9q) (P = 0.02). Interestingly, downregulation of TLE4 was not limited to AML with del(9q), potentially representing a common mechanism in AML pathogenesis. Our comprehensive genetic analysis of the del(9q) subgroup reveals a unique mutational profile with the frequency of DNMT3A mutations in the del(9q) only subset being the highest reported so far in AML, indicating oncogenic cooperativity. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Tobias Herold
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Klaus H Metzeler
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sebastian Vosberg
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Luise Hartmann
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Vindi Jurinovic
- Institute for Medical Informatics, Biometry and Epidemiology, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Sabrina Opatz
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Nikola P Konstandin
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Stephanie Schneider
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Evelyn Zellmeier
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Bianka Ksienzyk
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Alexander Graf
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Stefan Krebs
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Helmut Blum
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | | | - Thomas Büchner
- Department of Medicine A-Hematology, Oncology and Pneumology, University of Münster, Münster, Germany
| | - Wolfgang E Berdel
- Department of Medicine A-Hematology, Oncology and Pneumology, University of Münster, Münster, Germany
| | - Bernhard J Wörmann
- Department of Hematology, Oncology and Tumor Immunology, Charité University Medicine, Campus Virchow, Berlin, Germany
| | - Ulrich Mansmann
- German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute for Medical Informatics, Biometry and Epidemiology, Ludwig-Maximilians-Universität (LMU) München, München, Germany
| | - Wolfgang Hiddemann
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Stefan K Bohlander
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
| | - Karsten Spiekermann
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Philipp A Greif
- Department of Internal Medicine 3, University Hospital Grosshadern, Ludwig-Maximilians-Universität (LMU) München, München, Germany.,Clinical Cooperative Group Leukemia, Helmholtz Center Munich for Environmental Health, München, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
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20
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Shin TH, Brynczka C, Dayyani F, Rivera MN, Sweetser DA. TLE4 regulation of wnt-mediated inflammation underlies its role as a tumor suppressor in myeloid leukemia. Leuk Res 2016; 48:46-56. [PMID: 27486062 DOI: 10.1016/j.leukres.2016.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/07/2016] [Accepted: 07/19/2016] [Indexed: 12/27/2022]
Abstract
The presence of AML1-ETO (RUNX1-CBF2T1), a fusion oncoprotein resulting from a t(8;21) chromosomal translocation, has been implicated as a necessary but insufficient event in the development of a subset of acute myeloid leukemias (AML). While AML1-ETO prolongs survival and inhibits differentiation of hematopoietic stem cells (HSC), other contributory events are needed for cell proliferation and leukemogenesis. We have postulated that specific tumor suppressor genes keep the leukemic potential of AML1-ETO in check. In studying del(9q), one of the most common concomitant chromosomal abnormalities with t(8;21), we identified the loss of an apparent tumor suppressor, TLE4, that appears to cooperate with AML1-ETO to confer a leukemic phenotype. This study sought to identify the molecular basis of this cooperation. We show that the loss of TLE4 confers proliferative advantage to leukemic cells, simultaneous with an upregulation of a pro- inflammatory signature mediated through aberrant increases in Wnt signaling activity. We further demonstrate that inhibition of cyclooxygenase (COX) activity partly reverses the pro-leukemic phenotype due to TLE4 knockdown, pointing towards a novel therapeutic approach for myeloid leukemia.
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Affiliation(s)
- Thomas H Shin
- Department of Pediatrics, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, United States; Department of Molecular and Translational Medicine, Boston University School of Medicine, Boston, MA 02118, United States
| | - Christopher Brynczka
- Department of Pediatrics, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, United States
| | - Farshid Dayyani
- Department of Pediatrics, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, United States
| | - Miguel N Rivera
- Department of Pathology, Molecular Pathology Unit, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - David A Sweetser
- Department of Pediatrics, Divisions of Pediatric Hematology/Oncology and Medical Genetics, Massachusetts General Hospital, Boston, MA 02114, United States.
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21
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Abstract
The recent genomic characterization of cancers has revealed recurrent somatic point mutations and copy number changes affecting genes encoding RNA splicing factors. Initial studies of these 'spliceosomal mutations' suggest that the proteins bearing these mutations exhibit altered splice site and/or exon recognition preferences relative to their wild-type counterparts, resulting in cancer-specific mis-splicing. Such changes in the splicing machinery may create novel vulnerabilities in cancer cells that can be therapeutically exploited using compounds that can influence the splicing process. Further studies to dissect the biochemical, genomic and biological effects of spliceosomal mutations are crucial for the development of cancer therapies targeted at these mutations.
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Affiliation(s)
- Heidi Dvinge
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Eunhee Kim
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Leukemia Service, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Robert K. Bradley
- Computational Biology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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22
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Abstract
More than 60 Rab GTPases exist in the human genome to regulate vesicle trafficking between organelles. Rab GTPases are members of the Ras GTPase superfamily that broadly control budding, uncoating, motility and fusion of vesicles in most cell types. Rab proteins interconvert between active, GTP-bound form and inactive, GDP-bound form. In their active conformation, they interact with various effector molecules to carry out diverse functions. Rab GTPases are usually small containing only a GTPase domain with a C-terminal prenylation site for membrane anchoring. Recently, we identified a large G protein, CRACR2A (CRAC channel regulator 2A), which uncovers novel functions of Rab GTPases. First, CRACR2A encodes a large Rab GTPase containing multiple functional domains contrary to small Rab GTPases. Second, CRACR2A plays an unexpected role in regulating intracellular signaling pathways important for T cell activation, unlike the canonical role of small Rab GTPases. Vesicles containing CRACR2A bud out from the proximal Golgi area and translocate into the immunological synapse to activate these signaling pathways. Third, instead of recycling, CRACR2A is consumed by a unidirectional pathway. These events are sequentially regulated by prenylation, GTP binding, protein interaction with a signaling adaptor Vav1, and degradation. Together, our findings reveal a novel function of a large Rab GTPase in intracellular signaling pathways, which may be shared by other large Rab GTPases, Rab44 and Rab45.
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Affiliation(s)
- Sonal Srikanth
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
| | - Jin Seok Woo
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
| | - Yousang Gwack
- a Department of Physiology , David Geffen School of Medicine, UCLA , Los Angeles , CA , USA
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23
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Srikanth S, Kim KD, Gao Y, Woo JS, Ghosh S, Calmettes G, Paz A, Abramson J, Jiang M, Gwack Y. A large Rab GTPase encoded by CRACR2A is a component of subsynaptic vesicles that transmit T cell activation signals. Sci Signal 2016; 9:ra31. [PMID: 27016526 DOI: 10.1126/scisignal.aac9171] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
More than 60 members of the Rab family of guanosine triphosphatases (GTPases) exist in the human genome. Rab GTPases are small proteins that are primarily involved in the formation, trafficking, and fusion of vesicles. We showed thatCRACR2A(Ca(2+) release-activated Ca(2+) channel regulator 2A) encodes a lymphocyte-specific large Rab GTPase that contains multiple functional domains, including EF-hand motifs, a proline-rich domain (PRD), and a Rab GTPase domain with an unconventional prenylation site. Through experiments involving gene silencing in cells and knockout mice, we demonstrated a role for CRACR2A in the activation of the Ca(2+) and c-Jun N-terminal kinase signaling pathways in response to T cell receptor (TCR) stimulation. Vesicles containing this Rab GTPase translocated from near the Golgi to the immunological synapse formed between a T cell and a cognate antigen-presenting cell to activate these signaling pathways. The interaction between the PRD of CRACR2A and the guanidine nucleotide exchange factor Vav1 was required for the accumulation of these vesicles at the immunological synapse. Furthermore, we demonstrated that GTP binding and prenylation of CRACR2A were associated with its localization near the Golgi and its stability. Our findings reveal a previously uncharacterized function of a large Rab GTPase and vesicles near the Golgi in TCR signaling. Other GTPases with similar domain architectures may have similar functions in T cells.
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Affiliation(s)
- Sonal Srikanth
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA.
| | - Kyun-Do Kim
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Yuanyuan Gao
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Jin Seok Woo
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Shubhamoy Ghosh
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Guillaume Calmettes
- Department of Medicine (Cardiology), David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA
| | - Aviv Paz
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Jeff Abramson
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Meisheng Jiang
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, CA 90095, USA
| | - Yousang Gwack
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA.
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24
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Tle1 tumor suppressor negatively regulates inflammation in vivo and modulates NF-κB inflammatory pathway. Proc Natl Acad Sci U S A 2016; 113:1871-6. [PMID: 26831087 DOI: 10.1073/pnas.1511380113] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Tle1 (transducin-like enhancer of split 1) is a corepressor that interacts with a variety of DNA-binding transcription factors and has been implicated in many cellular functions; however, physiological studies are limited. Tle1-deficient (Tle1(Δ/Δ)) mice, although grossly normal at birth, exhibit skin defects, lung hypoplasia, severe runting, poor body condition, and early mortality. Tle1(Δ/Δ) mice display a chronic inflammatory phenotype with increased expression of inflammatory cytokines and chemokines in the skin, lung, and intestine and increased circulatory IL-6 and G-CSF, along with a hematopoietic shift toward granulocyte macrophage progenitor and myeloid cells. Tle1(Δ/Δ) macrophages produce increased inflammatory cytokines in response to Toll-like receptor (TLR) agonists and lipopolysaccharides (LPS), and Tle1(Δ/Δ) mice display an enhanced inflammatory response to ear skin 12-O-tetradecanoylphorbol-13-acetate treatment. Loss of Tle1 not only results in increased phosphorylation and activation of proinflammatory NF-κB but also results in decreased Hes1 (hairy and enhancer of split-1), a negative regulator of inflammation in macrophages. Furthermore, Tle1(Δ/Δ) mice exhibit accelerated growth of B6-F10 melanoma xenografts. Our work provides the first in vivo evidence, to our knowledge, that TLE1 is a major counterregulator of inflammation with potential roles in a variety of inflammatory diseases and in cancer progression.
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25
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Gallardo M, Lee HJ, Zhang X, Bueso-Ramos C, Pageon LR, McArthur M, Multani A, Nazha A, Manshouri T, Parker-Thornburg J, Rapado I, Quintas-Cardama A, Kornblau SM, Martinez-Lopez J, Post SM. hnRNP K Is a Haploinsufficient Tumor Suppressor that Regulates Proliferation and Differentiation Programs in Hematologic Malignancies. Cancer Cell 2015; 28:486-499. [PMID: 26412324 PMCID: PMC4652598 DOI: 10.1016/j.ccell.2015.09.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 04/14/2015] [Accepted: 09/01/2015] [Indexed: 12/20/2022]
Abstract
hnRNP K regulates cellular programs, and changes in its expression and mutational status have been implicated in neoplastic malignancies. To directly examine its role in tumorigenesis, we generated a mouse model harboring an Hnrnpk knockout allele (Hnrnpk(+/-)). Hnrnpk haploinsufficiency resulted in reduced survival, increased tumor formation, genomic instability, and the development of transplantable hematopoietic neoplasms with myeloproliferation. Reduced hnRNP K expression attenuated p21 activation, downregulated C/EBP levels, and activated STAT3 signaling. Additionally, analysis of samples from primary acute myeloid leukemia patients harboring a partial deletion of chromosome 9 revealed a significant decrease in HNRNPK expression. Together, these data implicate hnRNP K in the development of hematological disorders and suggest hnRNP K acts as a tumor suppressor.
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Affiliation(s)
- Miguel Gallardo
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hun Ju Lee
- Department of Lymphoma & Myeloma, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xiaorui Zhang
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Carlos Bueso-Ramos
- Department of Histopathology, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Laura R Pageon
- Department of Veterinary Medicine & Surgery, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mark McArthur
- Department of Veterinary Medicine & Surgery, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Asha Multani
- Department of Genetics, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Aziz Nazha
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Taghi Manshouri
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jan Parker-Thornburg
- Department of Genetics, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Inmaculada Rapado
- Department of Hematology, Hospital Universitario 12 de Octubre and CNIO, Madrid 28041, Spain
| | - Alfonso Quintas-Cardama
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Steven M Kornblau
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Joaquin Martinez-Lopez
- Department of Hematology, Hospital Universitario 12 de Octubre and CNIO, Madrid 28041, Spain
| | - Sean M Post
- Department of Leukemia, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA.
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26
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Pua HH, Krishnamurthi S, Farrell J, Margeta M, Ursell PC, Powers M, Slavotinek AM, Jeng LJB. Novel interstitial 2.6 Mb deletion on 9q21 associated with multiple congenital anomalies. Am J Med Genet A 2015; 164A:237-42. [PMID: 24501764 DOI: 10.1002/ajmg.a.36230] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Array comparative genomic hybridization (aCGH) is now commonly used to identify copy number changes in individuals with developmental delay, intellectual disabilities, autism spectrum disorders, and/or multiple congenital anomalies. We report on an infant with multiple congenital anomalies and a novel 2.6 Mb interstitial deletion within 9q21.32q21.33 detected by aCGH. Her clinical presentation included dysmorphic craniofacial features, cleft palate, atrial septal defect, bicornuate uterus, bilateral hip dislocation, hypotonia, and recurrent pneumonia. Parental aCGH studies were negative for copy loss in this region. To our knowledge, no similar deletions have been reported in available databases or published literature. This deletion encompasses 12 genes, and prediction algorithms as well as experimental data suggest that a subset is likely to be haploinsufficient. Included are a neurotrophin receptor (NKG2D), a gene implicated in cilia function (KIF27), an adaptor protein important for ubiquitin-dependent protein quality control (UBQLN1), a gene important for transcription and signaling (HNRNPK), and a gene involved in maintaining genomic stability (RMI1). Identifying additional patients with similar copy losses and further study of these genes will contribute to a better understanding of the pathophysiology of multiple congenital anomalies.
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27
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A Case of AML-M2 with Sole Interstitial Deletion in 9q Without AML1-ETO/Inv 16 Rearrangement and FLT3/NPMI Mutations. Indian J Hematol Blood Transfus 2014; 30:186-9. [PMID: 25332574 DOI: 10.1007/s12288-013-0322-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 12/24/2013] [Indexed: 11/27/2022] Open
Abstract
Conventional/molecular cytogenetics is important in identification of genomic abnormalities, for prognostication and in risk stratification of de novo patients with acute myeloid leukemias (AML). Here we present an AML M2 case showing the sole karyotypic abnormality, the rare interstitial deletion in the long arm of chromosome 9 with the loss of segment q12-q13.
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Zallot R, Brochier-Armanet C, Gaston KW, Forouhar F, Limbach PA, Hunt JF, de Crécy-Lagard V. Plant, animal, and fungal micronutrient queuosine is salvaged by members of the DUF2419 protein family. ACS Chem Biol 2014; 9:1812-25. [PMID: 24911101 PMCID: PMC4136680 DOI: 10.1021/cb500278k] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
![]()
Queuosine (Q) is a modification found
at the wobble position of
tRNAs with GUN anticodons. Although Q is present in most eukaryotes
and bacteria, only bacteria can synthesize Q de novo. Eukaryotes acquire queuine (q), the free base of Q, from diet and/or
microflora, making q an important but under-recognized micronutrient
for plants, animals, and fungi. Eukaryotic type tRNA-guanine transglycosylases
(eTGTs) are composed of a catalytic subunit (QTRT1) and a homologous
accessory subunit (QTRTD1) forming a complex that catalyzes q insertion
into target tRNAs. Phylogenetic analysis of eTGT subunits revealed
a patchy distribution pattern in which gene losses occurred independently
in different clades. Searches for genes co-distributing with eTGT
family members identified DUF2419 as a potential Q salvage protein
family. This prediction was experimentally validated in Schizosaccharomyces
pombe by confirming that Q was present by analyzing tRNAAsp with anticodon GUC purified from wild-type cells and by
showing that Q was absent from strains carrying deletions in the QTRT1
or DUF2419 encoding genes. DUF2419 proteins occur in most Eukarya
with a few possible cases of horizontal gene transfer to bacteria.
The universality of the DUF2419 function was confirmed by complementing
the S. pombe mutant with the Zea mays (maize), human, and Sphaerobacter thermophilus homologues.
The enzymatic function of this family is yet to be determined, but
structural similarity with DNA glycosidases suggests a ribonucleoside
hydrolase activity.
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Affiliation(s)
- Rémi Zallot
- Department
of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611, United States
| | - Céline Brochier-Armanet
- Université
Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie
Evolutive, Université de Lyon, 69622 Villeurbanne, France
| | - Kirk W. Gaston
- Rieveschl
Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Farhad Forouhar
- Department
of Biological Sciences and Northeast Structural Genomics Consortium, Columbia University, New York, New York 10027, United States
| | - Patrick A. Limbach
- Rieveschl
Laboratories for Mass Spectrometry, Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - John F. Hunt
- Department
of Biological Sciences and Northeast Structural Genomics Consortium, Columbia University, New York, New York 10027, United States
| | - Valérie de Crécy-Lagard
- Department
of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611, United States
- University of Florida Genetics Institute, Gainesville, Florida 32611, United States
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29
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Rohatgi N, Nielsen TK, Bjørn SP, Axelsson I, Paglia G, Voldborg BG, Palsson BO, Rolfsson Ó. Biochemical characterization of human gluconokinase and the proposed metabolic impact of gluconic acid as determined by constraint based metabolic network analysis. PLoS One 2014; 9:e98760. [PMID: 24896608 PMCID: PMC4045858 DOI: 10.1371/journal.pone.0098760] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 05/06/2014] [Indexed: 11/19/2022] Open
Abstract
The metabolism of gluconate is well characterized in prokaryotes where it is known to be degraded following phosphorylation by gluconokinase. Less is known of gluconate metabolism in humans. Human gluconokinase activity was recently identified proposing questions about the metabolic role of gluconate in humans. Here we report the recombinant expression, purification and biochemical characterization of isoform I of human gluconokinase alongside substrate specificity and kinetic assays of the enzyme catalyzed reaction. The enzyme, shown to be a dimer, had ATP dependent phosphorylation activity and strict specificity towards gluconate out of 122 substrates tested. In order to evaluate the metabolic impact of gluconate in humans we modeled gluconate metabolism using steady state metabolic network analysis. The results indicate that significant metabolic flux changes in anabolic pathways linked to the hexose monophosphate shunt (HMS) are induced through a small increase in gluconate concentration. We argue that the enzyme takes part in a context specific carbon flux route into the HMS that, in humans, remains incompletely explored. Apart from the biochemical description of human gluconokinase, the results highlight that little is known of the mechanism of gluconate metabolism in humans despite its widespread use in medicine and consumer products.
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Affiliation(s)
- Neha Rohatgi
- Center for Systems Biology, University of Iceland, Reykjavik, Iceland
- University of Iceland Biomedical Center, Reykjavik, Iceland
| | - Tine Kragh Nielsen
- Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sara Petersen Bjørn
- Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ivar Axelsson
- Center for Systems Biology, University of Iceland, Reykjavik, Iceland
| | - Giuseppe Paglia
- Center for Systems Biology, University of Iceland, Reykjavik, Iceland
| | - Bjørn Gunnar Voldborg
- Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Óttar Rolfsson
- Center for Systems Biology, University of Iceland, Reykjavik, Iceland
- University of Iceland Biomedical Center, Reykjavik, Iceland
- * E-mail:
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30
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Inferring the metabolism of human orphan metabolites from their metabolic network context affirms human gluconokinase activity. Biochem J 2013; 449:427-35. [PMID: 23067238 DOI: 10.1042/bj20120980] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Metabolic network reconstructions define metabolic information within a target organism and can therefore be used to address incomplete metabolic information. In the present study we used a computational approach to identify human metabolites whose metabolism is incomplete on the basis of their detection in humans but exclusion from the human metabolic network reconstruction RECON 1. Candidate solutions, composed of metabolic reactions capable of explaining the metabolism of these compounds, were then identified computationally from a global biochemical reaction database. Solutions were characterized with respect to how metabolites were incorporated into RECON 1 and their biological relevance. Through detailed case studies we show that biologically plausible non-intuitive hypotheses regarding the metabolism of these compounds can be proposed in a semi-automated manner, in an approach that is similar to de novo network reconstruction. We subsequently experimentally validated one of the proposed hypotheses and report that C9orf103, previously identified as a candidate tumour suppressor gene, encodes a functional human gluconokinase. The results of the present study demonstrate how semi-automatic gap filling can be used to refine and extend metabolic reconstructions, thereby increasing their biological scope. Furthermore, we illustrate how incomplete human metabolic knowledge can be coupled with gene annotation in order to prioritize and confirm gene functions.
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31
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Shaffer LG, Ballif BC, Schultz RA. The use of cytogenetic microarrays in myelodysplastic syndrome characterization. Methods Mol Biol 2013; 973:69-85. [PMID: 23412784 DOI: 10.1007/978-1-62703-281-0_5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Various microarray platforms, including BAC, oligonucleotide, and SNP arrays, have been shown to -provide clinically useful diagnostic and prognostic information for patients with myelodysplastic syndromes (MDS). Clinically useful arrays are designed with specific purposes in mind and with attention to genomic content and probe density. All array types have been shown to detect genomic copy gains and losses, with SNP arrays having the added advantage of detecting copy neutral loss of heterozygosity (CNLOH). The finding of CNLOH has led to the identification of certain disease genes implicated in the initiation or progression of myeloid diseases. In addition, SNP karyotyping alone, or in conjunction with routine cytogenetics, can affect the outcome prediction and improve prognostic stratification of patients with MDS. Patients who were reclassified after array testing as having adverse-risk chromosomal findings correlated with poor survival. Results of over 25 published studies support the use of arrays in MDS testing. Because few balanced translocations are found in MDS, this disease is particularly amenable to microarray testing, and studies have shown better disease classification, identification of cryptic changes, and prognostication in this heterogeneous group of disorders. Novel genomic alterations identified by array testing may lead to better targeted therapies for treating patients with MDS.
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Affiliation(s)
- Lisa G Shaffer
- Signature Genomic Laboratories, PerkinElmer Inc., Spokane, WA, USA.
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32
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Huh J, Mun YC, Seong CM, Chung WS. ABL1 deletion without BCR/ABL1 rearrangement is originated from a large-sized 9q deletion. Ann Hematol 2012; 91:1813-5. [PMID: 22453304 DOI: 10.1007/s00277-012-1450-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 03/11/2012] [Indexed: 10/28/2022]
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33
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Nakamura S, Takemura T, Tan L, Nagata Y, Yokota D, Hirano I, Shigeno K, Shibata K, Fujie M, Fujisawa S, Ohnishi K. Small GTPase RAB45-mediated p38 activation in apoptosis of chronic myeloid leukemia progenitor cells. Carcinogenesis 2011; 32:1758-72. [PMID: 21890458 DOI: 10.1093/carcin/bgr205] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Chronic myelogenous leukemia (CML) is characterized by a reciprocal chromosomal translocation (9;22) that generates the Bcr-Abl fusion gene. BCR-ABL transforming activity is mediated by critical downstream signaling pathways that are aberrantly activated by tyrosine kinases. However, the mechanisms of BCR-ABL anti-apoptotic effects and the signaling pathways by which BCR-ABL influences apoptosis in BCR-ABL-expressing cells are poorly defined. In this study, we found that treatment with ABL kinase inhibitors or depletion of BCR-ABL induced the expression of RAB45 messenger RNA and protein and induced apoptosis via reduction of mitochondrial membrane potential and p38 activation in CML cell lines and BCR-ABL(+) progenitor cells from CML patients. Overexpressed RAB45 induced the activation of caspases-3 and -9 and reduced the expression of Survivin, XIAP, c-IAP1 and c-IAP2 in CML cells. Moreover, in colony-forming cells derived from CML-aldehyde dehydrogenase(hi)/CD34(+) cells, treatment with ABL kinase inhibitors induced RAB45 expression and reduced mitochondrial membrane potential, resulting in inhibited colony formation of Bcr-Abl(+) progenitor cells. The overexpression of RAB45 significantly decreased colony numbers and induced apoptosis through the activation of caspases-3 and -9. Furthermore, the overexpression of RAB45 increased the phosphorylation levels of p38, resulting in the induction of apoptosis and inhibition of proliferation of CML progenitor cells. Our results identify a new signaling molecule involved in BCR-ABL modulation of apoptosis and suggest that RAB45 induction strategies may have therapeutic utility in patients with CML.
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MESH Headings
- Apoptosis/physiology
- Base Sequence
- Blotting, Western
- Caspase 3/metabolism
- Cell Cycle
- Cell Line, Tumor
- Cell Proliferation
- DNA Primers
- Enzyme Activation
- Genes, abl
- Humans
- Immunoprecipitation
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Membrane Potentials
- Neoplastic Stem Cells/pathology
- Phosphorylation
- RNA Interference
- RNA, Messenger/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- p38 Mitogen-Activated Protein Kinases/metabolism
- ras Guanine Nucleotide Exchange Factors/genetics
- ras Guanine Nucleotide Exchange Factors/physiology
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Affiliation(s)
- Satoki Nakamura
- Department of Internal Medicine III, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan.
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Acute myeloid leukemia with the t(8;21) translocation: clinical consequences and biological implications. J Biomed Biotechnol 2011; 2011:104631. [PMID: 21629739 PMCID: PMC3100545 DOI: 10.1155/2011/104631] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 01/31/2011] [Accepted: 02/22/2011] [Indexed: 12/20/2022] Open
Abstract
The t(8;21) abnormality occurs in a minority of acute myeloid leukemia (AML) patients. The translocation results in an in-frame fusion of two genes, resulting in a fusion protein of one N-terminal domain from the AML1 gene and four C-terminal domains from the ETO gene. This protein has multiple effects on the regulation of the proliferation, the differentiation, and the viability of leukemic cells. The translocation can be detected as the only genetic abnormality or as part of more complex abnormalities. If t(8;21) is detected in a patient with bone marrow pathology, the diagnosis AML can be made based on this abnormality alone. t(8;21) is usually associated with a good prognosis. Whether the detection of the fusion gene can be used for evaluation of minimal residual disease and risk of leukemia relapse remains to be clarified. To conclude, detection of t(8;21) is essential for optimal handling of these patients as it has both diagnostic, prognostic, and therapeutic implications.
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35
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Incomplete DNA methylation underlies a transcriptional memory of somatic cells in human iPS cells. Nat Cell Biol 2011; 13:541-9. [PMID: 21499256 DOI: 10.1038/ncb2239] [Citation(s) in RCA: 446] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 03/16/2011] [Indexed: 02/07/2023]
Abstract
Human induced pluripotent stem (iPS) cells are remarkably similar to embryonic stem (ES) cells, but recent reports indicate that there may be important differences between them. We carried out a systematic comparison of human iPS cells generated from hepatocytes (representative of endoderm), skin fibroblasts (mesoderm) and melanocytes (ectoderm). All low-passage iPS cells analysed retain a transcriptional memory of the original cells. The persistent expression of somatic genes can be partially explained by incomplete promoter DNA methylation. This epigenetic mechanism underlies a robust form of memory that can be found in iPS cells generated by multiple laboratories using different methods, including RNA transfection. Incompletely silenced genes tend to be isolated from other genes that are repressed during reprogramming, indicating that recruitment of the silencing machinery may be inefficient at isolated genes. Knockdown of the incompletely reprogrammed gene C9orf64 (chromosome 9 open reading frame 64) reduces the efficiency of human iPS cell generation, indicating that somatic memory genes may be functionally relevant during reprogramming.
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36
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Identification of acquired copy number alterations and uniparental disomies in cytogenetically normal acute myeloid leukemia using high-resolution single-nucleotide polymorphism analysis. Leukemia 2009; 24:438-49. [PMID: 20016533 DOI: 10.1038/leu.2009.263] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Recent advances in genome-wide single-nucleotide polymorphism (SNP) analyses have revealed previously unrecognized microdeletions and uniparental disomy (UPD) in a broad spectrum of human cancers. As acute myeloid leukemia (AML) represents a genetically heterogeneous disease, this technology might prove helpful, especially for cytogenetically normal AML (CN-AML) cases. Thus, we performed high-resolution SNP analyses in 157 adult cases of CN-AML. Regions of acquired UPDs were identified in 12% of cases and in the most frequently affected chromosomes, 6p, 11p and 13q. Notably, acquired UPD was invariably associated with mutations in nucleophosmin 1 (NPM1) or CCAAT/enhancer binding protein-alpha (CEBPA) that impair hematopoietic differentiation (P=0.008), suggesting that UPDs may preferentially target genes that are essential for proliferation and survival of hematopoietic progenitors. Acquired copy number alterations (CNAs) were detected in 49% of cases with losses found in two or more cases affecting, for example, chromosome bands 3p13-p14.1 and 12p13. Furthermore, we identified two cases with a cryptic t(6;11) as well as several non-recurrent aberrations pointing to leukemia-relevant regions. With regard to clinical outcome, there seemed to be an association between UPD 11p and UPD 13q cases with overall survival. These data show the potential of high-resolution SNP analysis for identifying genomic regions of potential pathogenic and clinical relevance in AML.
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37
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38
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Oldenburg RA, Kroeze-Jansema KHG, Houwing-Duistermaat JJ, Bayley JP, Dambrot C, van Asperen CJ, van den Ouweland AMW, Bakker B, van Beers EH, Nederlof PM, Vasen H, Hoogerbrugge N, Cornelisse CJ, Meijers-Heijboer H, Devilee P. Genome-wide linkage scan in Dutch hereditary non-BRCA1/2 breast cancer families identifies 9q21-22 as a putative breast cancer susceptibility locus. Genes Chromosomes Cancer 2008; 47:947-56. [PMID: 18663745 DOI: 10.1002/gcc.20597] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Breast cancer accounts for over 20% of all female cancers. A positive family history remains one of the most important risk factors for the disease, with first-degree relatives of patients having a twofold elevated risk. Known breast cancer susceptibility genes such as BRCA1 and BRCA2 explain only 20-25% of this risk, suggesting the existence of other breast cancer susceptibility genes. Here, we report the results of a genome-wide linkage scan in 55 high-risk Dutch breast cancer families with no mutations in BRCA1 and BRCA2. Twenty-two of these families were also part of a previous linkage study by the Breast Cancer Linkage Consortium. In addition, we performed CGH analyses in 61 tumors of these families and 31 sporadic tumors. Three regions were identified with parametric HLOD scores >1, and three with nonparametric LOD scores >1.5. Upon further marker genotyping for the candidate loci, and the addition of another 30 families to the analysis, only the locus on chromosome 9 (9q21-22, marker D9S167) remained significant, with a nonparametric multipoint LOD score of 3.96 (parametric HLOD 0.56, alpha = 0.18). With CGH analyses we observed preferential copy number loss at BAC RP11-276H19, containing D9S167 in familial tumors as compared to sporadic tumors (P < 0.001). Five candidate genes were selected from the region around D9S167 and their coding regions subjected to direct sequence analysis in 16 probands. No clear pathogenic mutations were found in any of these genes.
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Affiliation(s)
- Rogier A Oldenburg
- Center for Human and Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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39
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Wong JC, Le Beau MM, Shannon K. Tumor suppressor gene inactivation in myeloid malignancies. Best Pract Res Clin Haematol 2008; 21:601-14. [DOI: 10.1016/j.beha.2008.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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40
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Fraga MF, Berdasco M, Ballestar E, Ropero S, Lopez-Nieva P, Lopez-Serra L, Martín-Subero JI, Calasanz MJ, Lopez de Silanes I, Setien F, Casado S, Fernandez AF, Siebert R, Stifani S, Esteller M. Epigenetic inactivation of the Groucho homologue gene TLE1 in hematologic malignancies. Cancer Res 2008; 68:4116-22. [PMID: 18519670 DOI: 10.1158/0008-5472.can-08-0085] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An undifferentiated status and the epigenetic inactivation of tumor-suppressor genes are hallmarks of transformed cells. Promoter CpG island hypermethylation of differentiating genes, however, has rarely been reported. The Groucho homologue Transducin-like Enhancer of Split 1 (TLE1) is a multitasked transcriptional corepressor that acts through the acute myelogenous leukemia 1, Wnt, and Notch signaling pathways. We have found that TLE1 undergoes promoter CpG island hypermethylation-associated inactivation in hematologic malignancies, such as diffuse large B-cell lymphoma and AML. We also observed a mutual exclusivity of the epigenetic alteration of TLE1 and the cytogenetic alteration of AML1. TLE1 reintroduction in hypermethylated leukemia/lymphoma cells causes growth inhibition in colony assays and nude mice, whereas TLE1-short hairpin RNA depletion in unmethylated cells enhances tumor growth. We also show that these effects are mediated by TLE1 transcriptional repressor activity on its target genes, such as Cyclin D1, Colony-Stimulating Factor 1 receptor, and Hairy/Enhancer of Split 1. These data suggest that TLE1 epigenetic inactivation contributes to the development of hematologic malignancies by disrupting critical differentiation and growth-suppressing pathways.
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Affiliation(s)
- Mario F Fraga
- Cancer Epigenetics Laboratory, Spanish National Cancer Research Centre, Madrid, Spain
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41
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Loss of TLE1 and TLE4 from the del(9q) commonly deleted region in AML cooperates with AML1-ETO to affect myeloid cell proliferation and survival. Blood 2008; 111:4338-47. [PMID: 18258796 DOI: 10.1182/blood-2007-07-103291] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Deletions on chromosome 9q are seen in a subset of acute myeloid leukemia (AML) cases and are specifically associated with t(8;21) AML. We previously defined the commonly deleted region in del(9q) AML and characterized the genes in this interval. To determine the critical lost gene(s) that might cooperate with the AML1-ETO fusion gene produced by t(8;21), we developed a set of shRNAs directed against each gene in this region. Within this library, shRNAs to TLE1 and TLE4 were the only shRNAs capable of rescuing AML1-ETO expressing U937T-A/E cells from AML1-ETO-induced cell-cycle arrest and apoptosis. Knockdown of TLE1 or TLE4 levels increased the rate of cell division of the AML1-ETO-expressing Kasumi-1 cell line, whereas forced expression of either TLE1 or TLE4 caused apoptosis and cell death. Knockdown of Gro3, a TLE homolog in zebrafish, cooperated with AML1-ETO to cause an accumulation of noncirculating hematopoietic blast cells. Our data are consistent with a model in which haploinsufficiency of these TLEs overcomes the negative survival and antiproliferative effects of AML1-ETO on myeloid progenitors, allowing preleukemic stem cells to expand into AML. This study is the first to implicate the TLEs as potential tumor suppressor genes in myeloid leukemia.
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42
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Han M, Liew CT, Zhang HW, Chao S, Zheng R, Yip KT, Song ZY, Li HM, Geng XP, Zhu LX, Lin JJ, Marshall KW, Liew CC. Novel blood-based, five-gene biomarker set for the detection of colorectal cancer. Clin Cancer Res 2008; 14:455-60. [PMID: 18203981 DOI: 10.1158/1078-0432.ccr-07-1801] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
PURPOSE We applied a unique method to identify genes expressed in whole blood that can serve as biomarkers to detect colorectal cancer (CRC). EXPERIMENTAL DESIGN Total RNA was isolated from 211 blood samples (110 non-CRC, 101 CRC). Microarray and quantitative real-time PCR were used for biomarker screening and validation, respectively. RESULTS From a set of 31 RNA samples (16 CRC, 15 controls), we selected 37 genes from analyzed microarray data that differed significantly between CRC samples and controls (P < 0.05). We tested these genes with a second set of 115 samples (58 CRC, 57 controls) using quantitative real-time PCR, validating 17 genes as differentially expressed. Five of these genes were selected for logistic regression analysis, of which two were the most up-regulated (CDA and MGC20553) and three were the most down-regulated (BANK1, BCNP1, and MS4A1) in CRC patients. Logit (P) of the five-gene panel had an area under the curve of 0.88 (95% confidence interval, 0.81-0.94). At a cutoff of logit (P) >+0.5 as disease (high risk), <-0.5 as control (low risk), and in between as an intermediate zone, the five-gene biomarker combination yielded a sensitivity of 94% (47 of 50) and a specificity of 77% (33 of 43). The intermediate zone contained 22 samples. We validated the predictive power of these five genes with a novel third set of 92 samples, correctly identifying 88% (30 of 34) of CRC samples and 64% (27 of 42) of non-CRC samples. The intermediate zone contained 16 samples. CONCLUSION Our results indicate that the five-gene biomarker panel can be used as a novel blood-based test for CRC.
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Affiliation(s)
- Mark Han
- GeneNews Corporation, Toronto, ON, Canada
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43
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Bullinger L, Rücker FG, Kurz S, Du J, Scholl C, Sander S, Corbacioglu A, Lottaz C, Krauter J, Fröhling S, Ganser A, Schlenk RF, Döhner K, Pollack JR, Döhner H. Gene-expression profiling identifies distinct subclasses of core binding factor acute myeloid leukemia. Blood 2007; 110:1291-300. [PMID: 17485551 DOI: 10.1182/blood-2006-10-049783] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Core binding factor (CBF) leukemias, characterized by either inv(16)/t(16;16) or t(8;21), constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, there exists substantial biologic and clinical heterogeneity within these cytogenetic groups that is not fully reflected by the current classification system. To improve the molecular characterization we profiled gene expression in a large series (n = 93) of AML patients with CBF leukemia [(inv (16), n = 55; t(8;21), n = 38)]. By unsupervised hierarchical clustering we were able to define a subgroup of CBF cases (n = 35) characterized by shorter overall survival times (P = .03). While there was no obvious correlation with fusion gene transcript levels, FLT3 tyrosine kinase domain, KIT, and NRAS mutations, the newly defined inv(16)/t(8;21) subgroup was associated with elevated white blood cell counts and FLT3 internal tandem duplications (P = .011 and P = .026, respectively). Supervised analyses of gene expression suggested alternative cooperating pathways leading to transformation. In the "favorable" CBF leukemias, antiapoptotic mechanisms and deregulated mTOR signaling and, in the newly defined "unfavorable" subgroup, aberrant MAPK signaling and chemotherapy-resistance mechanisms might play a role. While the leukemogenic relevance of these signatures remains to be validated, their existence nevertheless supports a prognostically relevant biologic basis for the heterogeneity observed in CBF leukemia.
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Affiliation(s)
- Lars Bullinger
- Department of Internal Medicine III, University of Ulm, Ulm, Germany.
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