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Clinical Significance and Biological Role of HuR in Head and Neck Carcinomas. DISEASE MARKERS 2018; 2018:4020937. [PMID: 29619127 PMCID: PMC5829322 DOI: 10.1155/2018/4020937] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/27/2017] [Indexed: 12/17/2022]
Abstract
Background Hu-antigen R (HuR) is a posttranscriptional regulator of several target mRNAs, implicated in carcinogenesis. This review aims to present the current evidence regarding the biological role and potential clinical significance of HuR in head and neck carcinomas. Methods The existing literature concerning HuR expression and function in head and neck carcinomas is critically presented and summarised. Results HuR is expressed in the majority of the examined samples, showing higher cytoplasmic levels in malignant or premalignant cases. Moreover, HuR modulates several genes implicated in biological processes important for malignant transformation, growth, and invasiveness. HuR seems to be an adverse prognosticator in patients with OSCCs, whereas a correlation with a more aggressive phenotype is reported in several types of carcinomas. Conclusions A consistent role of HuR in the carcinogenesis and progression of head and neck carcinomas is suggested; nevertheless, further studies are warranted to expand the present information.
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Liu Y, Chen X, Cheng R, Yang F, Yu M, Wang C, Cui S, Hong Y, Liang H, Liu M, Zhao C, Ding M, Sun W, Liu Z, Sun F, Zhang C, Zhou Z, Jiang X, Chen X. The Jun/miR-22/HuR regulatory axis contributes to tumourigenesis in colorectal cancer. Mol Cancer 2018; 17:11. [PMID: 29351796 PMCID: PMC5775639 DOI: 10.1186/s12943-017-0751-3] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/26/2017] [Indexed: 12/11/2022] Open
Abstract
Background Colorectal cancer (CRC) is a severe health problem worldwide. Clarifying the mechanisms for the deregulation of oncogenes and tumour suppressors in CRC is vital for its diagnosis, treatment, prognosis and prevention. Hu antigen R (HuR), which is highly upregulated in CRC, functions as a pivotal oncogene to promote CRC progression. However, the underlying cause of its dysregulation is poorly understood. Methods In CRC tissue sample pairs, HuR protein levels were measured by Western blot and immunohistochemical (IHC) staining, respectively. HuR mRNA levels were also monitored by qRT-PCR. Combining meta-analysis and microRNA (miRNA) target prediction software, we predicted miRNAs that targeted HuR. Pull-down assay, Western blot and luciferase assay were utilized to demonstrate the direct binding of miR-22 on HuR’s 3’-UTR. The biological effects of HuR and miR-22 were investigated both in vitro by CCK-8, EdU and Transwell assays and in vivo by a xenograft mice model. JASPAR and SABiosciences were used to predict transcriptional factors that could affect miR-22. Luciferase assay was used to explore the validity of putative Jun binding sites for miR-22 regulation. ChIP assay was performed to test the Jun’s occupancy on the C17orf91 promoter. Results We observed a significant upregulation of HuR in CRC tissue pairs and confirmed the oncogenic function of HuR both in vitro and in vivo. We found that an important tumour-suppressive miRNA, miR-22, was significantly downregulated in CRC tissues and inversely correlated with HuR in both CRC tissues and CRC cell lines. We demonstrated that miR-22 directly bound to the 3’-UTR of HuR and led to inhibition of HuR protein, which repressed CRC proliferation and migration in vitro and decelerated CRC xenografted tumour growth in vivo. Furthermore, we found that the onco-transcription factor Jun could inhibit the transcription of miR-22. Conclusions Our findings highlight the critical roles of the Jun/miR-22/HuR regulatory axis in CRC progression and may provide attractive potential targets for CRC prevention and treatment. Electronic supplementary material The online version of this article (10.1186/s12943-017-0751-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yanqing Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Xiaorui Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Rongjie Cheng
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Fei Yang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Mengchao Yu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Chen Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Shufang Cui
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Yeting Hong
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Hongwei Liang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Minghui Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Chihao Zhao
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Meng Ding
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Wu Sun
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China
| | - Zhijian Liu
- Department of Gastrointestinal Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, 210008, China
| | - Feng Sun
- Department of Gastrointestinal Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, 210008, China
| | - Chenyu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Zhen Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
| | - Xiaohong Jiang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
| | - Xi Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
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Neelamraju Y, Gonzalez-Perez A, Bhat-Nakshatri P, Nakshatri H, Janga SC. Mutational landscape of RNA-binding proteins in human cancers. RNA Biol 2017; 15:115-129. [PMID: 29023197 PMCID: PMC5786023 DOI: 10.1080/15476286.2017.1391436] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
RNA Binding Proteins (RBPs) are a class of post-transcriptional regulatory molecules which are increasingly documented to be dysfunctional in cancer genomes. However, our current understanding of these alterations is limited. Here, we delineate the mutational landscape of ∼1300 RBPs in ∼6000 cancer genomes. Our analysis revealed that RBPs have an average of ∼3 mutations per Mb across 26 cancer types. We identified 281 RBPs to be enriched for mutations (GEMs) in at least one cancer type. GEM RBPs were found to undergo frequent frameshift and inframe deletions as well as missense, nonsense and silent mutations when compared to those that are not enriched for mutations. Functional analysis of these RBPs revealed the enrichment of pathways associated with apoptosis, splicing and translation. Using the OncodriveFM framework, we also identified more than 200 candidate driver RBPs that were found to accumulate functionally impactful mutations in at least one cancer. Expression levels of 15% of these driver RBPs exhibited significant difference, when transcriptome groups with and without deleterious mutations were compared. Functional interaction network of the driver RBPs revealed the enrichment of spliceosomal machinery, suggesting a plausible mechanism for tumorogenesis while network analysis of the protein interactions between RBPs unambiguously revealed the higher degree, betweenness and closeness centrality for driver RBPs compared to non-drivers. Analysis to reveal cancer-specific Ribonucleoprotein (RNP) mutational hotspots showed extensive rewiring even among common drivers between cancer types. Knockdown experiments on pan-cancer drivers such as SF3B1 and PRPF8 in breast cancer cell lines, revealed cancer subtype specific functions like selective stem cell features, indicating a plausible means for RBPs to mediate cancer-specific phenotypes. Hence, this study would form a foundation to uncover the contribution of the mutational spectrum of RBPs in dysregulating the post-transcriptional regulatory networks in different cancer types.
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Affiliation(s)
- Yaseswini Neelamraju
- a Department of Bio Health Informatics, School of Informatics and Computing , Indiana University Purdue University , Indianapolis , Indiana , USA
| | - Abel Gonzalez-Perez
- b Research Unit on Biomedical Informatics, Department of Experimental and Health Sciences , Universitat Pompeu Fabra , Barcelona , Spain
| | - Poornima Bhat-Nakshatri
- c Department of Surgery , Indiana University School of Medicine , Indianapolis , Indiana , USA
| | - Harikrishna Nakshatri
- c Department of Surgery , Indiana University School of Medicine , Indianapolis , Indiana , USA.,d Department of Biochemistry & Molecular Biology , Indiana University School of Medicine , Indianapolis , Indiana , USA.,e VA Roudebush Medical Center , Indianapolis , Indiana , USA
| | - Sarath Chandra Janga
- a Department of Bio Health Informatics, School of Informatics and Computing , Indiana University Purdue University , Indianapolis , Indiana , USA.,f Centre for Computational Biology and Bioinformatics , Indiana University School of Medicine , 5021 Health Information and Translational Sciences (HITS), Indianapolis , Indiana , USA.,g Department of Medical and Molecular Genetics , Indiana University School of Medicine , Medical Research and Library Building, Indianapolis , Indiana , USA
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Lee HC, Jung SH, Hwang HJ, Kang D, De S, Dudekula DB, Martindale JL, Park B, Park SK, Lee EK, Lee JH, Jeong S, Han K, Park HJ, Ko YG, Gorospe M, Lee JS. WIG1 is crucial for AGO2-mediated ACOT7 mRNA silencing via miRNA-dependent and -independent mechanisms. Nucleic Acids Res 2017; 45:6894-6910. [PMID: 28472401 PMCID: PMC5499809 DOI: 10.1093/nar/gkx307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 04/28/2017] [Indexed: 12/14/2022] Open
Abstract
RNA-binding proteins (RBPs) are involved in mRNA splicing, maturation, transport, translation, storage and turnover. Here, we identified ACOT7 mRNA as a novel target of human WIG1. ACOT7 mRNA decay was triggered by the microRNA miR-9 in a WIG1-dependent manner via classic recruitment of Argonaute 2 (AGO2). Interestingly, AGO2 was also recruited to ACOT7 mRNA in a WIG1-dependent manner in the absence of miR-9, which indicates an alternative model whereby WIG1 controls AGO2-mediated gene silencing. The WIG1–AGO2 complex attenuated translation initiation via an interaction with translation initiation factor 5B (eIF5B). These results were confirmed using a WIG1 tethering system based on the MS2 bacteriophage coat protein and a reporter construct containing an MS2-binding site, and by immunoprecipitation of WIG1 and detection of WIG1-associated proteins using liquid chromatography-tandem mass spectrometry. We also identified WIG1-binding motifs using photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation analyses. Altogether, our data indicate that WIG1 governs the miRNA-dependent and the miRNA-independent recruitment of AGO2 to lower the stability of and suppress the translation of ACOT7 mRNA.
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Affiliation(s)
- Hyung Chul Lee
- Department of Molecular Medicine, Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea
| | - Seung Hee Jung
- Department of Molecular Medicine, Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea
| | - Hyun Jung Hwang
- Department of Molecular Medicine, Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea
| | - Donghee Kang
- Department of Molecular Medicine, Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea
| | - Supriyo De
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, NIH, Baltimore, MD 21224, USA
| | - Dawood B Dudekula
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, NIH, Baltimore, MD 21224, USA
| | - Jennifer L Martindale
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, NIH, Baltimore, MD 21224, USA
| | - Byungkyu Park
- Department of Computer Science and Engineering, Inha University, Incheon 22212, Korea
| | - Seung Kuk Park
- Department of Molecular Biology, Dankook University, Yongin 16890, Korea
| | - Eun Kyung Lee
- Department of Biochemistry, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Jeong-Hwa Lee
- Department of Biochemistry, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Sunjoo Jeong
- Department of Molecular Biology, Dankook University, Yongin 16890, Korea
| | - Kyungsook Han
- Department of Computer Science and Engineering, Inha University, Incheon 22212, Korea
| | - Heon Joo Park
- Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Department of Microbiology, Inha University College of Medicine, Incheon 22212, Korea
| | - Young-Gyu Ko
- Division of Life Sciences, Korea University, Seoul 02841, Korea
| | - Myriam Gorospe
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, NIH, Baltimore, MD 21224, USA
| | - Jae-Seon Lee
- Department of Molecular Medicine, Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea.,Medical Research Center, Inha University College of Medicine, Incheon 22212, Korea
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55
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Effects of HuR downregulation on anaplastic thyroid cancer cells. Oncol Lett 2017; 15:575-579. [PMID: 29285201 DOI: 10.3892/ol.2017.7289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 09/01/2017] [Indexed: 02/07/2023] Open
Abstract
Anaplastic thyroid cancer (ATC) constitutes one of the most aggressive types of human solid cancer, and is characterized by the absence of thyroid differentiation features and a marked degree of invasiveness. We have previously demonstrated that the RNA-binding protein Hu antigen R (HuR) is overexpressed in thyroid carcinoma; thus, the biological role of this RNA-binding protein was investigated in the present study using the ATC cell lines SW1736 and 8505C. In both cell lines, HuR protein levels were higher compared with in the non-tumorigenic thyroid cell line Nthy-ori-3.1. HuR silencing by RNA interference in both ATC cell lines decreased cell viability, increased apoptosis rates and reduced the capability to form colonies in soft agar. Thus, HuR plays an important role in the proliferation and aggressiveness of ATC cells. The histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) was able to reduce the viability of ATC cells. The results demonstrated that SAHA was able to decrease HuR expression in SW1736 and 8505C cells. Furthermore, since it is known that the transcription factor nuclear factor (NF)-κB modulates HuR expression, whether SAHA affects the nuclear (active) fraction of NF-κB in ATC cells was investigated. The data suggested that SAHA decreases ATC cell viability by reducing the active form of NF-κB, which, in turn, modulates HuR expression.
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56
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Zhou RB, Lu XL, Zhang CY, Yin DC. RNA binding motif protein 3: a potential biomarker in cancer and therapeutic target in neuroprotection. Oncotarget 2017; 8:22235-22250. [PMID: 28118608 PMCID: PMC5400660 DOI: 10.18632/oncotarget.14755] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 01/10/2017] [Indexed: 12/14/2022] Open
Abstract
RNA binding motif 3 (RBM3) is a highly conserved cold-induced RNA binding protein that is transcriptionally up-regulated in response to harsh stresses. Featured as RNA binding protein, RBM3 is involved in mRNA biogenesis as well as stimulating protein synthesis, promoting proliferation and exerting anti-apoptotic functions. Nowadays, accumulating immunohistochemically studies have suggested RBM3 function as a proto-oncogene that is associated with tumor progression and metastasis in various cancers. Moreover, emerging evidences have also indicated that RBM3 is equally effective in neuroprotection. In the present review, we provide an overview of current knowledge concerning the role of RBM3 in various cancers and neuroprotection. Additionally, its potential roles as a promising diagnostic marker for cancer and a possible therapeutic target for neuro-related diseases are discussed.
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Affiliation(s)
- Ren-Bin Zhou
- Key Laboratory for Space Bioscience & Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, PR China
| | - Xiao-Li Lu
- Key Laboratory for Space Bioscience & Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, PR China
| | - Chen-Yan Zhang
- Key Laboratory for Space Bioscience & Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, PR China
| | - Da-Chuan Yin
- Key Laboratory for Space Bioscience & Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, PR China
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57
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Davidson MA, Shanks EJ. 3q26-29 Amplification in head and neck squamous cell carcinoma: a review of established and prospective oncogenes. FEBS J 2017; 284:2705-2731. [PMID: 28317270 DOI: 10.1111/febs.14061] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/23/2017] [Accepted: 03/15/2017] [Indexed: 12/22/2022]
Abstract
Head and neck squamous cell carcinoma (HNSCC) is significantly underrepresented in worldwide cancer research, yet survival rates for the disease have remained static for over 50 years. Distant metastasis is often present at the time of diagnosis, and is the primary cause of death in cancer patients. In the absence of routine effective targeted therapies, the standard of care treatment remains chemoradiation in combination with (often disfiguring) surgery. A defining characteristic of HNSCC is the amplification of a region of chromosome 3 (3q26-29), which is consistently associated with poorer patient outcome. This review provides an overview of the role the 3q26-29 region plays in HNSCC, in terms of both known and as yet undiscovered processes, which may have potential clinical relevance.
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58
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Martinez-Useros J, Georgiev-Hristov T, Fernández-Aceñero MJ, Borrero-Palacios A, Indacochea A, Guerrero S, Li W, Cebrián A, Gómez del Pulgar T, Puime-Otin A, del Puerto-Nevado L, Rodríguez-Remírez M, Pérez N, Celdrán A, Gebauer F, Garcia-Foncillas J. UNR/CDSE1 expression as prognosis biomarker in resectable pancreatic ductal adenocarcinoma patients: A proof-of-concept. PLoS One 2017; 12:e0182044. [PMID: 28763470 PMCID: PMC5538752 DOI: 10.1371/journal.pone.0182044] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 07/11/2017] [Indexed: 12/25/2022] Open
Abstract
Pancreatic ductal adenocarcinoma is an aggressive form of pancreatic cancer and the fourth leading cause of cancer-related death. When possible, curative approaches are based on surgical resection, though not every patient is a candidate for surgery. There are clinical guidelines for the management of these patients that offer different treatment options depending on the clinical and pathologic characteristics. However, the survival rates seen in this kind of patients are still low. The CDSE1 gene is located upstream of NRAS and encodes an RNA-binding protein termed UNR. The aim of this study was to analyze UNR expression and its correlation with outcome in patients with resectable pancreatic ductal adenocarcinoma (PDAC). For this, samples from resectable PDAC patients who underwent duodenopancreatectomy were used to evaluate UNR protein expression by immunohistochemistry using a tissue microarray. Here, we observed that low UNR expression was significantly associated with shorter progression-free survival after surgery (P = 0.010). Moreover, this prognostic marker remained significant after Cox proportional hazards model (P = 0.036). We further studied the role of CDSE1 expression in patient's prognosis using data from public repositories (GEO and TGCA), confirming our results. Interestingly, CDSE1 expression correlated with that of genes characteristic of an immunogenic molecular subtype of pancreatic cancer. Based on these findings, UNR may be considered a potential prognostic biomarker for resectable PDAC and may serve to guide subsequent adjuvant treatment decisions.
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Affiliation(s)
- Javier Martinez-Useros
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | | | | | - Aurea Borrero-Palacios
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - Alberto Indacochea
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Oncology and Molecular Pathology Research Group-VHIR- Vall d' Hebron Institut de Recerca-Vall d' Hebron Hospital, P/ de la Vall d'Hebron, Barcelona, Spain
| | - Santiago Guerrero
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Weiyao Li
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - Arancha Cebrián
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - Teresa Gómez del Pulgar
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - Alberto Puime-Otin
- Department of Pathology, University Hospital Fundacion Jimenez Diaz, Madrid, Spain
| | - Laura del Puerto-Nevado
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - María Rodríguez-Remírez
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
| | - Nuria Pérez
- Department of Pathology, University Hospital Fundacion Jimenez Diaz, Madrid, Spain
| | - Angel Celdrán
- Hepatobiliary and Pancreatic Surgery Unit, General and Digestive Tract Surgery Department, Fundacion Jimenez Diaz University Hospital, Madrid, Spain
| | - Fátima Gebauer
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Jesus Garcia-Foncillas
- Translational Oncology Division, OncoHealth Institute, University Hospital Fundacion Jimenez Diaz (FJD), Madrid, Spain
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Dang H, Takai A, Forgues M, Pomyen Y, Mou H, Xue W, Ray D, Ha KCH, Morris QD, Hughes TR, Wang XW. Oncogenic Activation of the RNA Binding Protein NELFE and MYC Signaling in Hepatocellular Carcinoma. Cancer Cell 2017; 32:101-114.e8. [PMID: 28697339 PMCID: PMC5539779 DOI: 10.1016/j.ccell.2017.06.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 04/18/2017] [Accepted: 06/08/2017] [Indexed: 02/06/2023]
Abstract
Global transcriptomic imbalance is a ubiquitous feature associated with cancer, including hepatocellular carcinoma (HCC). Analyses of 1,225 clinical HCC samples revealed that a large numbers of RNA binding proteins (RBPs) are dysregulated and that RBP dysregulation is associated with poor prognosis. We further identified that oncogenic activation of a top candidate RBP, negative elongation factor E (NELFE), via somatic copy-number alterations enhanced MYC signaling and promoted HCC progression. Interestingly, NELFE induces a unique tumor transcriptome by selectively regulating MYC-associated genes. Thus, our results revealed NELFE as an oncogenic protein that may contribute to transcriptome imbalance in HCC through the regulation of MYC signaling.
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Affiliation(s)
- Hien Dang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Atsushi Takai
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marshonna Forgues
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Yotsowat Pomyen
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Haiwei Mou
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Wen Xue
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Molecular Medicine, Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Debashish Ray
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Kevin C H Ha
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Quaid D Morris
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Timothy R Hughes
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Xin Wei Wang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
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Alshamsan A, Khan S, Imran A, Aljuffali IA, Alsaleh K. Prediction of Chlamydia pneumoniae protein localization in host mitochondria and cytoplasm and possible involvements in lung cancer etiology: a computational approach. Saudi Pharm J 2017; 25:1151-1157. [PMID: 30166903 PMCID: PMC6111117 DOI: 10.1016/j.jsps.2017.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 05/30/2017] [Indexed: 01/22/2023] Open
Abstract
Collecting evidence suggests that the intercellular infection of Chlamydia pneumoniae in lungs contributes to the etiology of lung cancer. Many proteins of Chlamydia pneumoniae outmanoeuvre the various system of the host. The infection may regulate various factors, which can influence the growth of lung cancer in affected persons. In this in-silico study, we predict potential targeting of Chlamydia pneumoniae proteins in mitochondrial and cytoplasmic comportments of host cell and their possible involvement in growth and development of lung cancer. Various cellular activities are controlled in mitochondria and cytoplasm, where the localization of Chlamydia pneumoniae proteins may alter the normal functioning of host cells. The rationale of this study is to find out and explain the connection between Chlamydia pneumoniae infection and lung cancer. A sum of 183 and 513 proteins were predicted to target in mitochondria and cytoplasm of host cell out of total 1112 proteins of Chlamydia pneumoniae. In particular, many targeted proteins may interfere with normal growth behaviour of host cells, thereby altering the decision of program cell death. Present article provides a potential connection of Chlamydia pneumoniae protein targeting and proposed that various targeted proteins may play crucial role in lung cancer etiology through diverse mechanisms.
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Affiliation(s)
- Aws Alshamsan
- Nanomedicine Research Unit, Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.,King Abdullah Institute for Nanotechnology, King Saud University, Riyadh, Saudi Arabia
| | - Shahanavaj Khan
- Nanomedicine Research Unit, Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Ahamad Imran
- King Abdullah Institute for Nanotechnology, King Saud University, Riyadh, Saudi Arabia
| | - Ibrahim A Aljuffali
- Nanomedicine Research Unit, Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Khalid Alsaleh
- Oncology Center, King Saud Medical City, King Saud University, Riyadh, Saudi Arabia
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61
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Analysis of post-transcriptional regulation during cancer progression using a donor-derived isogenic model of tumorigenesis. Methods 2017; 126:193-200. [PMID: 28529064 DOI: 10.1016/j.ymeth.2017.05.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 05/16/2017] [Indexed: 12/26/2022] Open
Abstract
Post-transcriptional regulation of gene expression by RNA binding proteins (RBPs) and non-coding RNAs plays an important role in global gene expression. Many post-transcriptional regulators are misexpressed and misregulated in cancers, resulting in altered programs of protein biosynthesis that can drive tumor progression. While comparative studies of several RBPs and microRNAs expressed in various cancer types have been reported, a model system that can be used to quantify RBP regulation and functional outcomes during the initiation and early stages of tumorigenesis is lacking. It was previously demonstrated that oncogenic transformation of normal human cells can be induced by expressing hTERT, p53DD, cyclin D1, CDK4R24C, C-MYCT58A and H-RASG12V. Here we describe a user-friendly method for generating this genetically defined model of step-wise tumorigenesis beginning with normal donor-derived human cells. This method immortalizes a donor's normal cells in about a week, reducing the chances of senescence. The entire stable system can be established in less than 12weeks. We then demonstrate the utility of such a system in elucidating the expression of multiple RBPs at an early step of tumor formation. We identify significant changes in the expression levels of transcripts encoding RBPs prior to transformation, suggesting that our described donor-derived isogenic system can provide insight about post-transcriptional regulation during the earliest stages of tumorigenesis in the context of diverse genetic backgrounds.
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62
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Vu LP, Prieto C, Amin EM, Chhangawala S, Krivtsov A, Calvo-Vidal MN, Chou T, Chow A, Minuesa G, Park SM, Barlowe TS, Taggart J, Tivnan P, Deering RP, Chu LP, Kwon JA, Meydan C, Perales-Paton J, Arshi A, Gönen M, Famulare C, Patel M, Paietta E, Tallman MS, Lu Y, Glass J, Garret-Bakelman FE, Melnick A, Levine R, Al-Shahrour F, Järås M, Hacohen N, Hwang A, Garippa R, Lengner CJ, Armstrong SA, Cerchietti L, Cowley GS, Root D, Doench J, Leslie C, Ebert BL, Kharas MG. Functional screen of MSI2 interactors identifies an essential role for SYNCRIP in myeloid leukemia stem cells. Nat Genet 2017; 49:866-875. [PMID: 28436985 PMCID: PMC5508533 DOI: 10.1038/ng.3854] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 03/31/2017] [Indexed: 12/15/2022]
Abstract
The identity of the RNA-binding proteins (RBPs) that govern cancer stem cells remains poorly characterized. The MSI2 RBP is a central regulator of translation of cancer stem cell programs. Through proteomic analysis of the MSI2-interacting RBP network and functional shRNA screening, we identified 24 genes required for in vivo leukemia. Syncrip was the most differentially required gene between normal and myeloid leukemia cells. SYNCRIP depletion increased apoptosis and differentiation while delaying leukemogenesis. Gene expression profiling of SYNCRIP-depleted cells demonstrated a loss of the MLL and HOXA9 leukemia stem cell program. SYNCRIP and MSI2 interact indirectly though shared mRNA targets. SYNCRIP maintains HOXA9 translation, and MSI2 or HOXA9 overexpression rescued the effects of SYNCRIP depletion. Altogether, our data identify SYNCRIP as a new RBP that controls the myeloid leukemia stem cell program. We propose that targeting these RBP complexes might provide a novel therapeutic strategy in leukemia.
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Affiliation(s)
- Ly P Vu
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Camila Prieto
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Physiology, Biophysics and Systems Biology Graduate Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, New York, USA
| | - Elianna M Amin
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Sagar Chhangawala
- Physiology, Biophysics and Systems Biology Graduate Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, New York, USA.,Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Andrei Krivtsov
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - M Nieves Calvo-Vidal
- Department of Medicine, Division of Hematology/Oncology, Weill Cornell Medical College, New York, New York, USA
| | - Timothy Chou
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Arthur Chow
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Gerard Minuesa
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Sun Mi Park
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Trevor S Barlowe
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - James Taggart
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Patrick Tivnan
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | | | - Lisa P Chu
- Division of Hematology, Brigham and Woman's Hospital, Boston, Massachusetts, USA
| | | | - Cem Meydan
- Institute for Computational Biomedicine, Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, USA
| | - Javier Perales-Paton
- Translational Bioinformatics Unit, Clinical Research Programme, Spanish National Cancer Research Centre, Madrid, Spain
| | - Arora Arshi
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Mithat Gönen
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Christopher Famulare
- Human Oncology and Pathogenesis Program, Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Minal Patel
- Human Oncology and Pathogenesis Program, Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Elisabeth Paietta
- Department of Medicine, Montefiore Medical Center, Bronx, New York, USA
| | - Martin S Tallman
- Leukemia Service, Department of Medicine, Memorial Sloan Kettering Hospital, New York, New York, USA
| | - Yuheng Lu
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Jacob Glass
- Leukemia Service, Department of Medicine, Memorial Sloan Kettering Hospital, New York, New York, USA
| | - Francine E Garret-Bakelman
- Department of Medicine and Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA.,Division of Hematology and Medical Oncology, Departments of Medicine and Pharmacology, Weill Cornell Medical College, Cornell University, New York, New York, USA
| | - Ari Melnick
- Division of Hematology and Medical Oncology, Departments of Medicine and Pharmacology, Weill Cornell Medical College, Cornell University, New York, New York, USA
| | - Ross Levine
- Human Oncology and Pathogenesis Program, Leukemia Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Fatima Al-Shahrour
- Translational Bioinformatics Unit, Clinical Research Programme, Spanish National Cancer Research Centre, Madrid, Spain
| | - Marcus Järås
- Department of Clinical Genetics, Lund University, Lund, Sweden
| | - Nir Hacohen
- Harvard Medical School, Boston, Massachusetts, USA
| | - Alexia Hwang
- RNAi Core, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ralph Garippa
- RNAi Core, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Christopher J Lengner
- Department of Animal Biology, Department of Cell and Developmental Biology, and Institute for Regenerative Medicine, Schools of Veterinary Medicine and Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Scott A Armstrong
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Leandro Cerchietti
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Glenn S Cowley
- Discovery Sciences, Janssen Research and Development, Spring House, Pennsylvania, USA
| | - David Root
- Broad Institute, Boston, Massachusetts, USA
| | | | - Christina Leslie
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Benjamin L Ebert
- Division of Hematology, Brigham and Woman's Hospital, Boston, Massachusetts, USA
| | - Michael G Kharas
- Molecular Pharmacology Program, Center for Cell Engineering, Center for Stem Cell Biology, and Center for Experimental Therapeutics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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Abstract
Mitochondria play fundamental roles in the regulation of life and death of eukaryotic cells. They mediate aerobic energy conversion through the oxidative phosphorylation (OXPHOS) system, and harbor and control the intrinsic pathway of apoptosis. As a descendant of a bacterial endosymbiont, mitochondria retain a vestige of their original genome (mtDNA), and its corresponding full gene expression machinery. Proteins encoded in the mtDNA, all components of the multimeric OXPHOS enzymes, are synthesized in specialized mitochondrial ribosomes (mitoribosomes). Mitoribosomes are therefore essential in the regulation of cellular respiration. Additionally, an increasing body of literature has been reporting an alternative role for several mitochondrial ribosomal proteins as apoptosis-inducing factors. No surprisingly, the expression of genes encoding for mitoribosomal proteins, mitoribosome assembly factors and mitochondrial translation factors is modified in numerous cancers, a trait that has been linked to tumorigenesis and metastasis. In this article, we will review the current knowledge regarding the dual function of mitoribosome components in protein synthesis and apoptosis and their association with cancer susceptibility and development. We will also highlight recent developments in targeting mitochondrial ribosomes for the treatment of cancer.
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64
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Maatz H, Kolinski M, Hubner N, Landthaler M. Transcriptome‐wide Identification of RNA‐binding Protein Binding Sites Using Photoactivatable‐Ribonucleoside‐Enhanced Crosslinking Immunoprecipitation (PAR‐CLIP). ACTA ACUST UNITED AC 2017; 118:27.6.1-27.6.19. [DOI: 10.1002/cpmb.35] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Henrike Maatz
- Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) Berlin Germany
| | - Marcin Kolinski
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) Berlin Germany
| | - Norbert Hubner
- Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) Berlin Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin Berlin Germany
- Charité Universitätsmedizin Berlin Germany
| | - Markus Landthaler
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) Berlin Germany
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65
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Lafzi A, Kazan H. Inferring RBP-Mediated Regulation in Lung Squamous Cell Carcinoma. PLoS One 2016; 11:e0155354. [PMID: 27186987 PMCID: PMC4871487 DOI: 10.1371/journal.pone.0155354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 04/27/2016] [Indexed: 12/11/2022] Open
Abstract
RNA-binding proteins (RBPs) play key roles in post-transcriptional regulation of mRNAs. Dysregulations in RBP-mediated mechanisms have been found to be associated with many steps of cancer initiation and progression. Despite this, previous studies of gene expression in cancer have ignored the effect of RBPs. To this end, we developed a lasso regression model that predicts gene expression in cancer by incorporating RBP-mediated regulation as well as the effects of other well-studied factors such as copy-number variation, DNA methylation, TFs and miRNAs. As a case study, we applied our model to Lung squamous cell carcinoma (LUSC) data as we found that there are several RBPs differentially expressed in LUSC. Including RBP-mediated regulatory effects in addition to the other features significantly increased the Spearman rank correlation between predicted and measured expression of held-out genes. Using a feature selection procedure that accounts for the adaptive search employed by lasso regularization, we identified the candidate regulators in LUSC. Remarkably, several of these candidate regulators are RBPs. Furthermore, majority of the candidate regulators have been previously found to be associated with lung cancer. To investigate the mechanisms that are controlled by these regulators, we predicted their target gene sets based on our model. We validated the target gene sets by comparing against experimentally verified targets. Our results suggest that the future studies of gene expression in cancer must consider the effect of RBP-mediated regulation.
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Affiliation(s)
- Atefeh Lafzi
- Department of Health Informatics, Middle East Technical University, Ankara, Turkey
| | - Hilal Kazan
- Department of Computer Engineering, Antalya International University, Antalya, Turkey
- * E-mail:
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66
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Hopkins TG, Mura M, Al-Ashtal HA, Lahr RM, Abd-Latip N, Sweeney K, Lu H, Weir J, El-Bahrawy M, Steel JH, Ghaem-Maghami S, Aboagye EO, Berman AJ, Blagden SP. The RNA-binding protein LARP1 is a post-transcriptional regulator of survival and tumorigenesis in ovarian cancer. Nucleic Acids Res 2016; 44:1227-46. [PMID: 26717985 PMCID: PMC4756840 DOI: 10.1093/nar/gkv1515] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 12/12/2015] [Accepted: 12/17/2015] [Indexed: 11/25/2022] Open
Abstract
RNA-binding proteins (RBPs) are increasingly identified as post-transcriptional drivers of cancer progression. The RBP LARP1 is an mRNA stability regulator, and elevated expression of the protein in hepatocellular and lung cancers is correlated with adverse prognosis. LARP1 associates with an mRNA interactome that is enriched for oncogenic transcripts. Here we explore the role of LARP1 in epithelial ovarian cancer, a disease characterized by the rapid acquisition of resistance to chemotherapy through the induction of pro-survival signalling. We show, using ovarian cell lines and xenografts, that LARP1 is required for cancer cell survival and chemotherapy resistance. LARP1 promotes tumour formation in vivo and maintains cancer stem cell-like populations. Using transcriptomic analysis following LARP1 knockdown, cross-referenced against the LARP1 interactome, we identify BCL2 and BIK as LARP1 mRNA targets. We demonstrate that, through an interaction with the 3' untranslated regions (3' UTRs) of BCL2 and BIK, LARP1 stabilizes BCL2 but destabilizes BIK with the net effect of resisting apoptosis. Together, our data indicate that by differentially regulating the stability of a selection of mRNAs, LARP1 promotes ovarian cancer progression and chemotherapy resistance.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Autoantigens/genetics
- Autoantigens/metabolism
- Blotting, Western
- Carcinogenesis/genetics
- Carcinogenesis/metabolism
- Cell Line, Tumor
- Cell Survival/drug effects
- Cell Survival/genetics
- Disease Progression
- Drug Resistance, Neoplasm/genetics
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Expression Regulation, Neoplastic/genetics
- HeLa Cells
- Humans
- Interleukin Receptor Common gamma Subunit/deficiency
- Interleukin Receptor Common gamma Subunit/genetics
- Mice, Inbred NOD
- Mice, Knockout
- Mice, SCID
- Microscopy, Confocal
- Ovarian Neoplasms/genetics
- Ovarian Neoplasms/metabolism
- Ovarian Neoplasms/pathology
- Protein Binding
- RNA Interference
- Reverse Transcriptase Polymerase Chain Reaction
- Ribonucleoproteins/genetics
- Ribonucleoproteins/metabolism
- Survival Analysis
- Transplantation, Heterologous
- SS-B Antigen
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Affiliation(s)
- Thomas G Hopkins
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Manuela Mura
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Hiba A Al-Ashtal
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Roni M Lahr
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Normala Abd-Latip
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Katrina Sweeney
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Haonan Lu
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Justin Weir
- Department of Histopathology, Imperial College Healthcare NHS Trust, London W12 0NN, UK
| | - Mona El-Bahrawy
- Department of Histopathology, Imperial College Healthcare NHS Trust, London W12 0NN, UK
| | - Jennifer H Steel
- Imperial College Experimental Cancer Medicine Centre, Division of Cancer, Imperial College Academic Health Science Centre, London W12 0NN, UK
| | - Sadaf Ghaem-Maghami
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK
| | - Eric O Aboagye
- Comprehensive Cancer Imaging Centre, Imperial College, Du Cane Road, London W12 0NN, UK
| | - Andrea J Berman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Sarah P Blagden
- Ovarian Cancer Action Research Centre, Institute of Reproductive and Developmental Biology, Imperial College, London W12 0HS, UK Department of Oncology, University of Oxford, Old Road, Oxford OX3 7LE, UK
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67
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Zurla C, Jung J, Santangelo PJ. Can we observe changes in mRNA "state"? Overview of methods to study mRNA interactions with regulatory proteins relevant in cancer related processes. Analyst 2016; 141:548-62. [PMID: 26605378 PMCID: PMC4701657 DOI: 10.1039/c5an01959a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
RNA binding proteins (RBP) regulate the editing, localization, stabilization, translation, and degradation of ribonucleic acids (RNA) through their interactions with specific cis-acting elements within target RNAs. Post-transcriptional regulatory mechanisms are directly involved in the control of the immune response and stress response and their alterations play a crucial role in cancer related processes. In this review, we discuss mRNAs and RNA binding proteins relevant to tumorigenesis, current methodologies for detecting RNA interactions, and last, we describe a novel method to detect such interactions, which combines peptide modified, RNA imaging probes (FMTRIPs) with proximity ligation (PLA) and rolling circle amplification (RCA). This assay detects native RNA in a sequence specific and single RNA sensitive manner, and PLA allows for the quantification and localization of protein-mRNA interactions with single-interaction sensitivity in situ.
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Affiliation(s)
- C Zurla
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, UA Whitaker Blgd, Atlanta, GA 30332, USA.
| | - J Jung
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, UA Whitaker Blgd, Atlanta, GA 30332, USA.
| | - P J Santangelo
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, UA Whitaker Blgd, Atlanta, GA 30332, USA.
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68
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Heterogeneous nuclear ribonucleoprotein A1 post-transcriptionally regulates Drp1 expression in neuroblastoma cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2015; 1849:1423-31. [PMID: 26518267 PMCID: PMC4655839 DOI: 10.1016/j.bbagrm.2015.10.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/04/2015] [Accepted: 10/23/2015] [Indexed: 12/22/2022]
Abstract
Excessive mitochondrial fission is associated with the pathogenesis of neurodegenerative diseases. Dynamin-related protein 1 (Drp1) possesses specific fission activity in the mitochondria and peroxisomes. Various post-translational modifications of Drp1 are known to modulate complex mitochondrial dynamics. However, the post-transcriptional regulation of Drp1 remains poorly understood. Here, we show that the heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) regulates Drp1 expression at the post-transcriptional level. hnRNP A1 directly interacts with Drp1 mRNA at its 3′UTR region, and enhances translation potential without affecting mRNA stability. Down-regulation of hnRNP A1 induces mitochondrial elongation by reducing Drp1 expression. Moreover, depletion of hnRNP A1 suppresses 3-NP-mediated mitochondrial fission and dysfunction. In contrast, over-expression of hnRNP A1 promotes mitochondrial fragmentation by increasing Drp1 expression. Additionally, hnRNP A1 significantly exacerbates 3-NP-induced mitochondrial dysfunction and cell death in neuroblastoma cells. Interestingly, treatment with 3-NP induces subcellular translocation of hnRNP A1 from the nucleus to the cytoplasm, which accelerates the increase in Drp1 expression in hnRNP A1 over-expressing cells. Collectively, our findings suggest that hnRNP A1 controls mitochondrial dynamics by post-transcriptional regulation of Drp1. hnRNP A1 increases Drp1 expression through the interaction with 3′UTR of Drp1 mRNA. Down-regulation of hnRNP A1 increases mitochondrial elongation by reducing drp1 expression. Down-regulation of hnRNPA1 inhibits 3-NP-mediated mitochondrial dysfunction. Over-expression of hnRNP A1 potentiates 3-NP-mediated mitochondrial dysfunction and cell death. Treatment of 3-NP promotes translocation of hnRNP A1 to the cytoplasm and enhances Drp1 expression.
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69
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Mura M, Hopkins TG, Michael T, Abd-Latip N, Weir J, Aboagye E, Mauri F, Jameson C, Sturge J, Gabra H, Bushell M, Willis AE, Curry E, Blagden SP. LARP1 post-transcriptionally regulates mTOR and contributes to cancer progression. Oncogene 2015; 34:5025-36. [PMID: 25531318 PMCID: PMC4430325 DOI: 10.1038/onc.2014.428] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 09/20/2014] [Accepted: 10/21/2014] [Indexed: 12/24/2022]
Abstract
RNA-binding proteins (RBPs) bind to and post-transcriptionally regulate the stability of mRNAs. La-related protein 1 (LARP1) is a conserved RBP that interacts with poly-A-binding protein and is known to regulate 5'-terminal oligopyrimidine tract (TOP) mRNA translation. Here, we show that LARP1 is complexed to 3000 mRNAs enriched for cancer pathways. A prominent member of the LARP1 interactome is mTOR whose mRNA transcript is stabilized by LARP1. At a functional level, we show that LARP1 promotes cell migration, invasion, anchorage-independent growth and in vivo tumorigenesis. Furthermore, we show that LARP1 expression is elevated in epithelial cancers such as cervical and non-small cell lung cancers, where its expression correlates with disease progression and adverse prognosis, respectively. We therefore conclude that, through the post-transcriptional regulation of genes such as mTOR within cancer pathways, LARP1 contributes to cancer progression.
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Affiliation(s)
- M Mura
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - T G Hopkins
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - T Michael
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - N Abd-Latip
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - J Weir
- Department of Cellular Pathology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK
| | - E Aboagye
- Division of Cancer, Department of Surgery and Cancer, Cancer Research UK Laboratories, Imperial College London, Hammersmith Campus, London, UK
| | - F Mauri
- Department of Histopathology, Centre for Pathology, Imperial College London, Hammersmith Campus, London, UK
| | - C Jameson
- Department of Histopathology, University College Hospital, London, UK
| | - J Sturge
- Division of Cancer, Department of Surgery and Cancer, Cancer Research UK Laboratories, Imperial College London, Hammersmith Campus, London, UK
- School of Biological, Biomedical & Environmental Sciences, The Allam Building, University of Hull, Hull, UK
| | - H Gabra
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - M Bushell
- MRC Toxicology Unit, Hodgkin Building, University of Leicester, Leicester, UK
| | - A E Willis
- MRC Toxicology Unit, Hodgkin Building, University of Leicester, Leicester, UK
| | - E Curry
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
| | - S P Blagden
- Division of Cancer, Department of Surgery and Cancer, Ovarian Cancer Action Research Centre, Imperial College London, Hammersmith Campus, London, UK
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Wang Z, Bhattacharya A, Ivanov DN. Identification of Small-Molecule Inhibitors of the HuR/RNA Interaction Using a Fluorescence Polarization Screening Assay Followed by NMR Validation. PLoS One 2015; 10:e0138780. [PMID: 26390015 PMCID: PMC4577092 DOI: 10.1371/journal.pone.0138780] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 09/03/2015] [Indexed: 01/25/2023] Open
Abstract
The human antigen R (HuR) stabilizes many mRNAs of proto-oncogene, transcription factors, cytokines and growth factors by recognizing AU-rich elements (AREs) presented in their 3’ or 5’ untranslated region (UTR). Multiple lines of experimental evidence suggest that this process plays a key role in cancer development. Thus, destabilizing HuR/RNA interaction by small molecules presents an opportunity for cancer treatment/prevention. Here we present an integrated approach to identify inhibitors of HuR/RNA interaction using a combination of fluorescence-based and NMR-based high throughput screening (HTS). The HTS assay with fluorescence polarization readout and Z’-score of 0.8 was used to perform a screen of the NCI diversity set V library in a 384 well plate format. An NMR-based assay with saturation transfer difference (STD) detection was used for hits validation. Protein NMR spectroscopy was used to demonstrate that some hit compounds disrupt formation of HuR oligomer, whereas others block RNA binding. Thus, our integrated high throughput approach provides a new avenue for identification of small molecules targeting HuR/RNA interaction.
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Affiliation(s)
- Zhonghua Wang
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, United States of America
- * E-mail:
| | - Akash Bhattacharya
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, United States of America
| | - Dmitri N. Ivanov
- Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, United States of America
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71
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Computational prediction of Escherichia coli proteins host subcellular targeting and their implications in colorectal cancer etiology. Cancer Lett 2015; 364:25-32. [DOI: 10.1016/j.canlet.2015.04.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/19/2015] [Accepted: 04/20/2015] [Indexed: 12/19/2022]
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72
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Wang J, Liu Q, Shyr Y. Dysregulated transcription across diverse cancer types reveals the importance of RNA-binding protein in carcinogenesis. BMC Genomics 2015; 16 Suppl 7:S5. [PMID: 26100984 PMCID: PMC4474540 DOI: 10.1186/1471-2164-16-s7-s5] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Background It is well known that carcinogenesis is in part dictated by dysregulated transcription events and signal pathways. Large-scale transcriptional profiling studies in each cancer type have reported aberrant gene expression associated with cancer development. However, common and specific patterns altered across cancer types, especially the contribution of transcriptional and post-transcriptional regulators, are rarely explored. Results Using transcriptional profiles from matched tumor and normal samples in the Cancer Genome Atlas pan-cancer dataset, we performed a comprehensive analysis on the altered expression across 9 cancer types, focusing on transcriptional and post-transcriptional regulators and cancer-related genes. As we expected, the transcription of cancer-related genes was significantly deregulated in tumor vs. normal across all cancer types. Surprisingly, the expression of RNA-binding proteins (RBPs), master regulators of post-transcriptional gene expression, was also significantly changed across most studied cancer types. Although the expression of RBPs was not as strongly deregulated as cancer-related genes, their direct interaction partners are enriched by cancer-related genes, suggesting the cascade regulation effect of RBPs. Integrating genetic and epigenetic profiles found that deregulated RBPs were frequently caused by genetic rather than epigenetic alterations. Furthermore, tissue-specific genes were under-expressed in tumor vs. normal across all cancer types except prostate cancer. Conclusions Dysregulated transcription across cancer types reveals the importance of RBPs in carcinogenesis. The aberrant expression of RBPs is caused by genetic alterations and spreads their effect to cancer-related genes. In addition, disruption of tissue-specific genes contributes to the corresponding cancer pathology.
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Abstract
Despite the rapid accumulation of tumor-profiling data and transcription factor (TF) ChIP-seq profiles, efforts integrating TF binding with the tumor-profiling data to understand how TFs regulate tumor gene expression are still limited. To systematically search for cancer-associated TFs, we comprehensively integrated 686 ENCODE ChIP-seq profiles representing 150 TFs with 7484 TCGA tumor data in 18 cancer types. For efficient and accurate inference on gene regulatory rules across a large number and variety of datasets, we developed an algorithm, RABIT (regression analysis with background integration). In each tumor sample, RABIT tests whether the TF target genes from ChIP-seq show strong differential regulation after controlling for background effect from copy number alteration and DNA methylation. When multiple ChIP-seq profiles are available for a TF, RABIT prioritizes the most relevant ChIP-seq profile in each tumor. In each cancer type, RABIT further tests whether the TF expression and somatic mutation variations are correlated with differential expression patterns of its target genes across tumors. Our predicted TF impact on tumor gene expression is highly consistent with the knowledge from cancer-related gene databases and reveals many previously unidentified aspects of transcriptional regulation in tumor progression. We also applied RABIT on RNA-binding protein motifs and found that some alternative splicing factors could affect tumor-specific gene expression by binding to target gene 3'UTR regions. Thus, RABIT (rabit.dfci.harvard.edu) is a general platform for predicting the oncogenic role of gene expression regulators.
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74
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Neelamraju Y, Hashemikhabir S, Janga SC. The human RBPome: from genes and proteins to human disease. J Proteomics 2015; 127:61-70. [PMID: 25982388 DOI: 10.1016/j.jprot.2015.04.031] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 04/07/2015] [Accepted: 04/28/2015] [Indexed: 12/29/2022]
Abstract
RNA binding proteins (RBPs) play a central role in mediating post transcriptional regulation of genes. However less is understood about them and their regulatory mechanisms. In this study, we construct a catalogue of 1344 experimentally confirmed RBPs. The domain architecture of RBPs enabled us to classify them into three groups - Classical (29%), Non-classical (19%) and unclassified (52%). A higher percentage of proteins with unclassified domains reveals the presence of various uncharacterised motifs that can potentially bind RNA. RBPs were found to be highly disordered compared to Non-RBPs (p<2.2e-16, Fisher's exact test), suggestive of a dynamic regulatory role of RBPs in cellular signalling and homeostasis. Evolutionary analysis in 62 different species showed that RBPs are highly conserved compared to Non-RBPs (p<2.2e-16, Wilcox-test), reflecting the conservation of various biological processes like mRNA splicing and ribosome biogenesis. The expression patterns of RBPs from human proteome map revealed that ~40% of them are ubiquitously expressed and ~60% are tissue-specific. RBPs were also seen to be highly associated with several neurological disorders, cancer and inflammatory diseases. Anatomical contexts like B cells, T-cells, foetal liver and foetal brain were found to be strongly enriched for RBPs, implying a prominent role of RBPs in immune responses and different developmental stages. The catalogue and meta-analysis presented here should form a foundation for furthering our understanding of RBPs and the cellular networks they control, in years to come. This article is part of a Special Issue entitled: Proteomics in India.
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Affiliation(s)
- Yaseswini Neelamraju
- Department of Biohealth Informatics School of Informatics and Computing, Indiana University Purdue University, 719 Indiana Ave Ste 319, Walker Plaza Building, Indianapolis, IN 46202, United States
| | - Seyedsasan Hashemikhabir
- Department of Biohealth Informatics School of Informatics and Computing, Indiana University Purdue University, 719 Indiana Ave Ste 319, Walker Plaza Building, Indianapolis, IN 46202, United States
| | - Sarath Chandra Janga
- Department of Biohealth Informatics School of Informatics and Computing, Indiana University Purdue University, 719 Indiana Ave Ste 319, Walker Plaza Building, Indianapolis, IN 46202, United States; Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, 5021 Health Information and Translational Sciences (HITS), 410 West 10th Street, Indianapolis, IN 46202, United States; Department of Medical and Molecular Genetics, Indiana University School of Medicine, Medical Research and Library Building, 975 West Walnut Street, Indianapolis, IN 46202, United States.
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75
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Wang T, Xiao G, Chu Y, Zhang MQ, Corey DR, Xie Y. Design and bioinformatics analysis of genome-wide CLIP experiments. Nucleic Acids Res 2015; 43:5263-74. [PMID: 25958398 PMCID: PMC4477666 DOI: 10.1093/nar/gkv439] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 04/23/2015] [Indexed: 01/05/2023] Open
Abstract
The past decades have witnessed a surge of discoveries revealing RNA regulation as a central player in cellular processes. RNAs are regulated by RNA-binding proteins (RBPs) at all post-transcriptional stages, including splicing, transportation, stabilization and translation. Defects in the functions of these RBPs underlie a broad spectrum of human pathologies. Systematic identification of RBP functional targets is among the key biomedical research questions and provides a new direction for drug discovery. The advent of cross-linking immunoprecipitation coupled with high-throughput sequencing (genome-wide CLIP) technology has recently enabled the investigation of genome-wide RBP–RNA binding at single base-pair resolution. This technology has evolved through the development of three distinct versions: HITS-CLIP, PAR-CLIP and iCLIP. Meanwhile, numerous bioinformatics pipelines for handling the genome-wide CLIP data have also been developed. In this review, we discuss the genome-wide CLIP technology and focus on bioinformatics analysis. Specifically, we compare the strengths and weaknesses, as well as the scopes, of various bioinformatics tools. To assist readers in choosing optimal procedures for their analysis, we also review experimental design and procedures that affect bioinformatics analyses.
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Affiliation(s)
- Tao Wang
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Guanghua Xiao
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Yongjun Chu
- Departments of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Michael Q Zhang
- Department of Biological Sciences, Center for Systems Biology, The University of Texas at Dallas, Richardson, TX 75080, USA Bioinformatics Division, Center for Synthetic and System Biology, TNLIST, Tsinghua University, Beijing 100084, China
| | - David R Corey
- Departments of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Yang Xie
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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Silipo M, Gautrey H, Tyson-Capper A. Deregulation of splicing factors and breast cancer development. J Mol Cell Biol 2015; 7:388-401. [PMID: 25948865 DOI: 10.1093/jmcb/mjv027] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 02/24/2015] [Indexed: 11/13/2022] Open
Abstract
It is well known that many genes implicated in the development and progression of breast cancer undergo aberrant alternative splicing events to produce proteins with pro-cancer properties. These changes in alternative splicing can arise from mutations or single-nucleotide polymorphisms (SNPs) within the DNA sequences of cancer-related genes, which can strongly affect the activity of splicing factors and influence the splice site choice. However, it is important to note that absence of mutations is not sufficient to prevent misleading choices in splice site selection. There is now increasing evidence to demonstrate that the expression profile of ten splicing factors (including SRs and hnRNPs) and eight RNA-binding proteins changes in breast cancer cells compared with normal cells. These modifications strongly influence the alternative splicing pattern of many cancer-related genes despite the absence of any detrimental mutations within their DNA sequences. Thus, a comprehensive assessment of the splicing factor status in breast cancer is important to provide insights into the mechanisms that lead to breast cancer development and metastasis. Whilst most studies focus on mutations that affect alternative splicing in cancer-related genes, this review focuses on splicing factors and RNA-binding proteins that are themselves deregulated in breast cancer and implicated in cancer-related alternative splicing events.
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Affiliation(s)
- Marco Silipo
- Institute of Cellular Medicine, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Hannah Gautrey
- Institute of Cellular Medicine, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Alison Tyson-Capper
- Institute of Cellular Medicine, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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77
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Marcel V, Catez F, Diaz JJ. p53, a translational regulator: contribution to its tumour-suppressor activity. Oncogene 2015; 34:5513-23. [DOI: 10.1038/onc.2015.25] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/08/2015] [Accepted: 01/12/2015] [Indexed: 12/14/2022]
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78
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Mice deficient in Rbm38, a target of the p53 family, are susceptible to accelerated aging and spontaneous tumors. Proc Natl Acad Sci U S A 2014; 111:18637-42. [PMID: 25512531 DOI: 10.1073/pnas.1415607112] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
RNA-binding motif protein 38 (Rbm38), also called RNPC1 [RNA-binding region (RNP1, RRM) containing 1], is a target of the p53 family and modulates p53 expression via mRNA translation. To investigate the biological function of Rbm38 in vivo, we generated an Rbm38-null mouse model. We showed that mice deficient in Rbm38 exhibit signs of accelerated aging and are prone to hematopoietic defects and spontaneous tumors. To determine the biological significance of the p53-Rbm38 loop, we showed that Rbm38 deficiency enhances accumulation of p53 induced by ionizing radiation (IR) and sensitizes mice to IR-induced lethality in a p53-dependent manner. Most importantly, Rbm38 deficiency markedly decreases the tumor penetrance in mice heterozygous for p53 via enhanced p53 expression. Interestingly, we found that Rbm38 deficiency shortens the life span of, and promotes lymphomagenesis in, mice deficient in p53. These results provide genetic evidence that Rbm38 is necessary for normal hematopoiesis and for suppressing accelerated aging and tumorigenesis. Thus, the p53-Rbm38 axis might be explored for extending longevity and for tumor suppression.
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79
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Wurth L, Gebauer F. RNA-binding proteins, multifaceted translational regulators in cancer. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:881-6. [PMID: 25316157 DOI: 10.1016/j.bbagrm.2014.10.001] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 10/01/2014] [Accepted: 10/04/2014] [Indexed: 12/21/2022]
Abstract
RNA-binding proteins (RBPs) orchestrate transcript fate and function. Even though alterations in post-transcriptional events contribute to key steps of tumor initiation and progression, RBP-mediated control has remained relatively unexplored in cancer. Here, we discuss examples of this promising field focusing on translation regulation, and highlight the variety of molecular mechanisms by which RBPs impinge on translation with consequences for tumorigenesis. This article is part of a Special Issue entitled: Translation and Cancer.
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Affiliation(s)
- Laurence Wurth
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Fátima Gebauer
- Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain.
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80
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Kloetgen A, Münch PC, Borkhardt A, Hoell JI, McHardy AC. Biochemical and bioinformatic methods for elucidating the role of RNA-protein interactions in posttranscriptional regulation. Brief Funct Genomics 2014; 14:102-14. [PMID: 24951655 PMCID: PMC4471435 DOI: 10.1093/bfgp/elu020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Our understanding of transcriptional gene regulation has dramatically increased over the past decades, and many regulators of gene expression, such as transcription factors, have been analyzed extensively. Additionally, in recent years, deeper insights into the physiological roles of RNA have been obtained. More precisely, splicing, polyadenylation, various modifications, localization and the translation of messenger RNAs (mRNAs) are regulated by their interaction with RNA-binding proteins (RBPs). New technologies now enable the analysis of this regulation at different levels. A technique known as ultraviolet (UV) cross-linking and immunoprecipitation (CLIP) allows us to determine physical protein–RNA interactions on a genome-wide scale. UV cross-linking introduces covalent bonds between interacting RBPs and RNAs. In combination with immunoprecipitation and deep sequencing techniques, tens of millions of short reads (representing bound RNAs by an RBP of interest) are generated and are used to characterize the regulatory network mediated by an RBP. Other methods, such as mass spectrometry, can also be used for characterization of cross-linked RBPs and RNAs instead of CLIP methods. In this review, we discuss experimental and computational methods for the generation and analysis of CLIP data. The computational methods include short-read alignment, annotation and RNA-binding motif discovery. We describe the challenges of analyzing CLIP data and indicate areas where improvements are needed.
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Affiliation(s)
| | | | | | | | - Alice C McHardy
- Corresponding author. Alice C. McHardy, Heinrich-Heine University, Department of Algorithmic Bioinformatics, Universitaetsstrasse 1, 40225 Duesseldorf, Germany. Tel.: +49-211-8110427; Fax: +49-211-8113464; E-mail:
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81
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Kechavarzi B, Janga SC. Dissecting the expression landscape of RNA-binding proteins in human cancers. Genome Biol 2014; 15:R14. [PMID: 24410894 PMCID: PMC4053825 DOI: 10.1186/gb-2014-15-1-r14] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 01/10/2014] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND RNA-binding proteins (RBPs) play important roles in cellular homeostasis by controlling gene expression at the post-transcriptional level. RESULTS We explore the expression of more than 800 RBPs in sixteen healthy human tissues and their patterns of dysregulation in cancer genomes from The Cancer Genome Atlas project. We show that genes encoding RBPs are consistently and significantly highly expressed compared with other classes of genes, including those encoding regulatory components such as transcription factors, miRNAs and long non-coding RNAs. We also demonstrate that a set of RBPs, numbering approximately 30, are strongly upregulated (SUR) across at least two-thirds of the nine cancers profiled in this study. Analysis of the protein-protein interaction network properties for the SUR and non-SUR groups of RBPs suggests that path length distributions between SUR RBPs is significantly lower than those observed for non-SUR RBPs. We further find that the mean path lengths between SUR RBPs increases in proportion to their contribution to prognostic impact. We also note that RBPs exhibiting higher variability in the extent of dysregulation across breast cancer patients have a higher number of protein-protein interactions. We propose that fluctuating RBP levels might result in an increase in non-specific protein interactions, potentially leading to changes in the functional consequences of RBP binding. Finally, we show that the expression variation of a gene within a patient group is inversely correlated with prognostic impact. CONCLUSIONS Overall, our results provide a roadmap for understanding the impact of RBPs on cancer pathogenesis.
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Affiliation(s)
- Bobak Kechavarzi
- Department of Biohealth Informatics, School of Informatics and Computing, Indiana University – Purdue University, 719 Indiana Ave Ste 319, Walker Plaza Building, Indianapolis, IN 46202, USA
| | - Sarath Chandra Janga
- Department of Biohealth Informatics, School of Informatics and Computing, Indiana University – Purdue University, 719 Indiana Ave Ste 319, Walker Plaza Building, Indianapolis, IN 46202, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, 5021 Health Information and Translational Sciences (HITS), 410 West 10th Street, Indianapolis, IN 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Medical Research and Library Building, 975 West Walnut Street, Indianapolis, IN 46202, USA
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82
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Jiang Y, Zhang M, Qian Y, Xu E, Zhang J, Chen X. Rbm24, an RNA-binding protein and a target of p53, regulates p21 expression via mRNA stability. J Biol Chem 2013; 289:3164-75. [PMID: 24356969 DOI: 10.1074/jbc.m113.524413] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
p21, a cyclin-dependent kinase inhibitor, is necessary for proper control of the cell cycle and premature senescence. Thus, p21 expression needs to be tightly controlled. In this study, we found that Rbm24, an RNA-binding protein and a target gene of the p53 protein, can regulate p21 expression via mRNA stability. Specifically, we showed that Rbm24 is induced by DNA damage and Mdm2 inhibitor Nutlin-3. We also found that p53 protein binds to and activates the promoter of the Rbm24 gene. Moreover, we found that overexpression of Rbm24 increases, whereas knockdown of Rbm24 decreases, p21 mRNA and protein expression. In addition, we demonstrated that overexpression of Rbm24 enhances the half-life of p21 transcript. Consistent with this, we provided evidence that Rbm24 binds to the 3'-untranslated region (3'-UTR) of p21 transcript and an AU/U-rich element in the p21 3'-UTR is necessary for Rbm24 to increase p21 expression. Finally, we showed that the RNA recognition motif in Rbm24 is required for binding to p21 transcript and subsequently for inducing p21 expression. Altogether, we uncovered that Rbm24 is a novel player in the p53 pathway, which may be explored to restore proper cell cycle control in p53-deficient tumors via p21.
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Affiliation(s)
- Yuqian Jiang
- From the Comparative Oncology Laboratory, University of California, Davis, California 95616
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83
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Winslow S, Leandersson K, Larsson C. Regulation of PMP22 mRNA by G3BP1 affects cell proliferation in breast cancer cells. Mol Cancer 2013; 12:156. [PMID: 24321297 PMCID: PMC3866477 DOI: 10.1186/1476-4598-12-156] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 11/27/2013] [Indexed: 12/21/2022] Open
Abstract
Background Regulation of mRNAs is one way to control protein levels and thereby important cellular processes such as growth, invasion and apoptosis. G3BPs constitute a family of mRNA-binding proteins, shown to be overexpressed in several cancer types, including breast, colon and pancreas cancer. G3BP has been reported to both stabilize and induce degradation of specific mRNAs. Results Here, we show that G3BP1, but not G3BP2, supports proliferation of several breast cancer cell lines. Global gene expression analyses of G3BP1- and G3BP2-depleted cells indicate that primarily G3BP1, and much less G3BP2, influences mRNA expression levels. Peripheral myelin protein 22 (PMP22) was one gene that was significantly influenced by G3BP1 depletion which led to a 2–3 fold increased expression. Depletion of PMP22 resulted in increased proliferation and the G3BP1-mediated effect on proliferation was not seen upon PMP22-depletion. Conclusions This indicates a novel role for G3BP1 in the regulation of cell proliferation in breast cancer cells, perhaps via a regulatory effect on PMP22 expression.
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Affiliation(s)
| | | | - Christer Larsson
- Department of Laboratory Medicine, Translational Cancer Research, Lund University, Medicon Village, Building 404:C3, Lund, 223 81, Sweden.
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84
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Vanderweyde T, Youmans K, Liu-Yesucevitz L, Wolozin B. Role of stress granules and RNA-binding proteins in neurodegeneration: a mini-review. Gerontology 2013; 59:524-33. [PMID: 24008580 DOI: 10.1159/000354170] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 07/03/2013] [Indexed: 12/13/2022] Open
Abstract
The eukaryotic stress response involves translational suppression of non-housekeeping proteins and the sequestration of unnecessary mRNA transcripts into stress granules (SGs). This process is dependent on mRNA-binding proteins (RBPs) that interact with capped mRNA transcripts through RNA recognition motifs, and exhibit reversible aggregation through hydrophobic polyglycine domains, some of which are homologous to yeast prion proteins. The activity and aggregation of RBPs appears to be important in the context of unfolded protein diseases. The discovery that mutations in these RBPs can cause familial motoneuron diseases and familial dementias indicates the importance of these genes to neuronal degeneration. Some disorders linked to mutations in RBPs include: amyotrophic lateral sclerosis, frontotemporal dementia and spinal muscular atrophy. These RBPs also associate with pathological structures in other neurodegenerative diseases, including Huntington's chorea, Creutzfeldt-Jakob disease, and Alzheimer's disease. Interestingly, protein levels of RBPs change across the aging spectrum and may be linked to other age-related disorders, such as type 2 diabetes. The link between SG pathways and proteins linked to neurodegenerative diseases suggests a potential role for common pathways in both processes, such as those involved in translational control, and highlights potentially novel targets for therapeutic intervention in neurodegenerative diseases.
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Affiliation(s)
- Tara Vanderweyde
- Department of Pharmacology, Boston University School of Medicine, Boston, Mass., USA
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85
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The RNA binding protein ESRP1 fine-tunes the expression of pluripotency-related factors in mouse embryonic stem cells. PLoS One 2013; 8:e72300. [PMID: 24015231 PMCID: PMC3755004 DOI: 10.1371/journal.pone.0072300] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 07/09/2013] [Indexed: 12/12/2022] Open
Abstract
In pluripotent stem cells, there is increasing evidence for crosstalk between post-transcriptional and transcriptional networks, offering multifold steps at which pluripotency can be controlled. In addition to well-studied transcription factors, chromatin modifiers and miRNAs, RNA-binding proteins are emerging as fundamental players in pluripotency regulation. Here, we report a new role for the RNA-binding protein ESRP1 in the control of pluripotency. Knockdown of Esrp1 in mouse embryonic stem cells induces, other than the well-documented epithelial to mesenchymal-like state, also an increase in expression of the core transcription factors Oct4, Nanog and Sox2, thereby enhancing self-renewal of these cells. Esrp1-depleted embryonic stem cells displayed impaired early differentiation in vitro and formed larger teratomas in vivo when compared to control embryonic stem cells. We also show that ESRP1 binds to Oct4 and Sox2 mRNAs and decreases their polysomal loading. ESRP1 thus acts as a physiological regulator of the finely-tuned balance between self-renewal and commitment to a restricted developmental fate. Importantly, both mouse and human epithelial stem cells highly express ESRP1, pinpointing the importance of this RNA-binding protein in stem cell biology.
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86
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Plakophilin-associated RNA-binding proteins in prostate cancer and their implications in tumor progression and metastasis. Virchows Arch 2013; 463:379-90. [PMID: 23881279 DOI: 10.1007/s00428-013-1452-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 07/01/2013] [Accepted: 07/08/2013] [Indexed: 01/04/2023]
Abstract
Both plakophilins (PKP) 1 and 3 play a role in the progression of prostate cancer. The RNA-binding proteins (RBPs) GAP-SH3-binding protein (G3BP), fragile-X-related protein 1 (FXR1), poly(A)-binding protein, cytoplasmic 1 (PABPC1), and up-frameshift factor 1 (UPF1) are associated with PKP3. All these RBPs have an impact on RNA metabolism. Until recently, the PKP-associated RBPs have not been analyzed in prostate cancer. In the current study, we showed by affinity purification that the PKP3-associated RBPs were also binding partners of PKP1. We examined the expression of PKP1/3-associated RBPs and PKP1/3 in prostate cell lines, tumor-free prostate, and 136 prostatic adenocarcinomas by immunofluorescence and immunoblot. All four RBPs G3BP, FXR1, UPF1, and PABPC1 were expressed in the glandular epithelium of the normal prostate. PKP1 and FXR1 were strongly reduced in tumor tissues with Gleason score >7 and diminished expression of PKP1 and FXR1 also appeared to be associated with a metastatic phenotype. Additionally, the predominant nuclear localization of UPF1 in normal glandular cells and low grade tumors was switched to a more cytoplasmic pattern in carcinomas with Gleason score >7. Our findings suggest that PKP1 and FXR1 may have a tumor-suppressive function and are downregulated in more aggressive tumors. Collectively, PKP1/3-associated RBPs FXR1 and UPF1 may have a functional role in prostate cancer progression and metastasis and highlight the potential importance of posttranscriptional regulation of gene expression and nonsense-mediated decay in cancer.
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EJC core component MLN51 interacts with eIF3 and activates translation. Proc Natl Acad Sci U S A 2013; 110:5903-8. [PMID: 23530232 DOI: 10.1073/pnas.1218732110] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The multiprotein exon junction complex (EJC), deposited by the splicing machinery, is an important constituent of messenger ribonucleoprotein particles because it participates to numerous steps of the mRNA lifecycle from splicing to surveillance via nonsense-mediated mRNA decay pathway. By an unknown mechanism, the EJC also stimulates translation efficiency of newly synthesized mRNAs. Here, we show that among the four EJC core components, the RNA-binding protein metastatic lymph node 51 (MLN51) is a translation enhancer. Overexpression of MLN51 preferentially increased the translation of intron-containing reporters via the EJC, whereas silencing MLN51 decreased translation. In addition, modulation of the MLN51 level in cell-free translational extracts confirmed its direct role in protein synthesis. Immunoprecipitations indicated that MLN51 associates with translation-initiating factors and ribosomal subunits, and in vitro binding assays revealed that MLN51, alone or as part of the EJC, interacts directly with the pivotal eukaryotic translation initiation factor eIF3. Taken together, our data define MLN51 as a translation activator linking the EJC and the translation machinery.
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Comparability of differential proteomics data generated from paired archival fresh-frozen and formalin-fixed samples by GeLC-MS/MS and spectral counting. J Proteomics 2012; 77:561-76. [PMID: 23043969 DOI: 10.1016/j.jprot.2012.09.033] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 09/17/2012] [Accepted: 09/22/2012] [Indexed: 11/22/2022]
Abstract
In this study, a Veterinary Department repository composed by paired formalin-fixed paraffin-embedded (FFPE) and fresh-frozen (FrFr) sets of the same tissues, routinely archived in the typical conditions of a clinical setting, was exploited to perform a comparative evaluation of the results generated by GeLC-MS/MS (1-DE followed by in-gel digestion and LC-MS/MS) and spectral counting with the two types of archival samples. Therefore, two parallel differential proteomic studies were performed using 3 canine mammary carcinomas and 3 normal controls in a paired fashion (6 FrFr and 6 FFPE in total). As a result, the FrFr and FFPE differential proteomic datasets exhibited fair consistency in differential expression trends, according to protein molecular function, cellular localization, networks, and pathways. However, FFPE samples were globally slightly less informative, especially concerning the high-MW subproteome. As a further investigation, new insights into the molecular aspects of protein fixation and retrieval were obtained. In conclusion, archival FFPE samples can be reliably used for differential proteomics studies employing a spectral counting GeLC-MS/MS approach, although some typical biases need to be taken into account, and FrFr specimens (when available) should still be considered as the gold standard for clinical proteomics.
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