1
|
Calvo Sánchez J, Köhn M. Small but Mighty-The Emerging Role of snoRNAs in Hematological Malignancies. Noncoding RNA 2021; 7:68. [PMID: 34842767 PMCID: PMC8629011 DOI: 10.3390/ncrna7040068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 11/16/2022] Open
Abstract
Over recent years, the long known class of small nucleolar RNAs (snoRNAs) have gained interest among the scientific community, especially in the clinical context. The main molecular role of this interesting family of non-coding RNAs is to serve as scaffolding RNAs to mediate site-specific RNA modification of ribosomal RNAs (rRNAs) and small nuclear RNAs (snRNAs). With the development of new sequencing techniques and sophisticated analysis pipelines, new members of the snoRNA family were identified and global expression patterns in disease backgrounds could be determined. We will herein shed light on the current research progress in snoRNA biology and their clinical role by influencing disease outcome in hematological diseases. Astonishingly, in recent studies snoRNAs emerged as potent biomarkers in a variety of these clinical setups, which is also highlighted by the frequent deregulation of snoRNA levels in the hema-oncological context. However, research is only starting to reveal how snoRNAs might influence cellular functions and the connected disease hallmarks in hematological malignancies.
Collapse
Affiliation(s)
| | - Marcel Köhn
- Junior Research Group ‘RBPs and ncRNAs in Human Diseases’, Medical Faculty, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Saale, Germany;
| |
Collapse
|
2
|
Liang Q, Du X, Mao L, Wang G. Molecular characterization of colorectal cancer: A five-gene prognostic signature based on RNA-binding proteins. Saudi J Gastroenterol 2021; 27:223-233. [PMID: 34169901 PMCID: PMC8448017 DOI: 10.4103/sjg.sjg_530_20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Colorectal cancer (CRC) is one of the most common cancers worldwide. RNA-binding proteins (RBPs) regulate essential biological processes and play essential roles in a variety of cancers. The present study screened differentially expressed RBPs, analyzed their function and constructed a prognostic model to predict the overall survival of patients with CRC. METHODS We downloaded CRC RNA-sequencing data from the Cancer Genome Atlas (TCGA) portal and screened differentially expressed RBPs. Then, functional analyses of these genes were performed, and a risk model was established by multivariate Cox regression. RESULTS We obtained 132 differentially expressed RBPs, including 66 upregulated and 66 downregulated RBPs. Functional analysis revealed that these genes were significantly enriched in RNA processing, modification and binding, ribosome biogenesis, post-transcriptional regulation, ribonuclease and nuclease activity. Additionally, some RBPs were significantly related to interferon (IFN)-alpha and IFN-beta biosynthetic processes and the Toll-like receptor signaling pathway. A prognostic model was constructed and included insulin like growth factor 2 messenger ribonucleic acid binding protein 3 (IGF2BP3), poly (A) binding protein cytoplasmic 1 like (PABPC1L), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PPARGC1A), peptidyl- transfer ribonucleic acid hydrolase 1 homolog (PTRH1) and tudor domain containing 7 (TDRD7). The model is an independent risk factor for clinicopathological characteristics. CONCLUSION Our study provided novel insights into the pathogenesis of CRC and constructed a prognostic gene model, which may be helpful for determining the prognosis of CRC.
Collapse
Affiliation(s)
- Qiankun Liang
- Gansu University of Chinese Medicine, Lanzhou, China,Address for correspondence: Dr. Qiankun Liang, Gansu University of Chinese Medicine, Lanzhou 730020, China. E-mail:
| | - Xiaojuan Du
- Gansu University of Chinese Medicine, Lanzhou, China
| | - Lanfang Mao
- Gansu University of Chinese Medicine, Lanzhou, China,Affiliated Hospital of Gansu University of Chinese Medicine, Lanzhou, China
| | | |
Collapse
|
3
|
Zhang X, Meng T, Cui S, Feng L, Liu D, Pang Q, Wang P. Ubiquitination of Nonhistone Proteins in Cancer Development and Treatment. Front Oncol 2021; 10:621294. [PMID: 33643919 PMCID: PMC7905169 DOI: 10.3389/fonc.2020.621294] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 12/24/2020] [Indexed: 12/14/2022] Open
Abstract
Ubiquitination, a crucial post-translation modification, regulates the localization and stability of the substrate proteins including nonhistone proteins. The ubiquitin-proteasome system (UPS) on nonhistone proteins plays a critical role in many cellular processes such as DNA repair, transcription, signal transduction, and apoptosis. Its dysregulation induces various diseases including cancer, and the identification of this process may provide potential therapeutic targets for cancer treatment. In this review, we summarize the regulatory roles of key UPS members on major nonhistone substrates in cancer-related processes, such as cell cycle, cell proliferation, apoptosis, DNA damage repair, inflammation, and T cell dysfunction in cancer. In addition, we also highlight novel therapeutic interventions targeting the UPS members (E1s, E2s, E3s, proteasomes, and deubiquitinating enzymes). Furthermore, we discuss the application of proteolysis-targeting chimeras (PROTACs) technology as a novel anticancer therapeutic strategy in modulating protein target levels with the aid of UPS.
Collapse
Affiliation(s)
- Xiuzhen Zhang
- School of Life Sciences, Shandong University of Technology, Zibo, China
| | - Tong Meng
- Tongji University Cancer Center, Shanghai Tenth People’s Hospital of Tongji University, School of Medicine, Tongji University, Shanghai, China
| | - Shuaishuai Cui
- School of Life Sciences, Shandong University of Technology, Zibo, China
| | - Ling Feng
- School of Life Sciences, Shandong University of Technology, Zibo, China
| | - Dongwu Liu
- School of Life Sciences, Shandong University of Technology, Zibo, China
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Qiuxiang Pang
- School of Life Sciences, Shandong University of Technology, Zibo, China
| | - Ping Wang
- School of Life Sciences, Shandong University of Technology, Zibo, China
| |
Collapse
|
4
|
Li KK, Mao CY, Ma Q, Bao T, Wang YJ, Guo W, Zhao XL. U three protein 14a (UTP14A) promotes tumour proliferation and metastasis via the PERK/eIF2a/GRP78 signalling pathway in oesophageal squamous cell carcinoma. J Cancer 2021; 12:134-140. [PMID: 33391409 PMCID: PMC7738832 DOI: 10.7150/jca.44649] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 08/29/2020] [Indexed: 12/22/2022] Open
Abstract
Metastasis and malignant proliferation are major obstacles to the treatment of oesophageal squamous cell carcinoma (ESCC), and UTP14A is associated with poor prognosis in ESCC. However, its mechanisms have not been fully elucidated. The TCGA and GEO databases were used to identify candidate target genes and possible downstream targets. Then, the effects were determined in vitro and in vivo through knockdown and overexpression techniques, and the mechanism was explored. UTP14A was significantly higher in the tumour tissue of ESCC patients than in normal tissue. Knockdown of UTP14A significantly suppressed the migration and proliferation of ESCC cells. The PERK/eIF2a signalling pathway was positively regulated by UTP14A, and its tumour-promoting effect was further activated by overexpression of UTP14A. In conclusion, UTP14A might promote the proliferation and metastasis of ESCC cells by inducing PERK/eIF2a signalling pathway expression.
Collapse
Affiliation(s)
- Kun-Kun Li
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, PR China
| | - Cheng-Yi Mao
- Department of Pathology, Daping Hospital, Army Medical University, PR China
| | - Qiang Ma
- Department of Pathology, Daping Hospital, Army Medical University, PR China
| | - Tao Bao
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, PR China
| | - Ying-Jian Wang
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, PR China
| | - Wei Guo
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, PR China
| | - Xiao-Long Zhao
- Department of Pathology, Daping Hospital, Army Medical University, PR China
| |
Collapse
|
5
|
Nait Slimane S, Marcel V, Fenouil T, Catez F, Saurin JC, Bouvet P, Diaz JJ, Mertani HC. Ribosome Biogenesis Alterations in Colorectal Cancer. Cells 2020; 9:E2361. [PMID: 33120992 PMCID: PMC7693311 DOI: 10.3390/cells9112361] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/24/2022] Open
Abstract
Many studies have focused on understanding the regulation and functions of aberrant protein synthesis in colorectal cancer (CRC), leaving the ribosome, its main effector, relatively underappreciated in CRC. The production of functional ribosomes is initiated in the nucleolus, requires coordinated ribosomal RNA (rRNA) processing and ribosomal protein (RP) assembly, and is frequently hyperactivated to support the needs in protein synthesis essential to withstand unremitting cancer cell growth. This elevated ribosome production in cancer cells includes a strong alteration of ribosome biogenesis homeostasis that represents one of the hallmarks of cancer cells. None of the ribosome production steps escape this cancer-specific dysregulation. This review summarizes the early and late steps of ribosome biogenesis dysregulations described in CRC cell lines, intestinal organoids, CRC stem cells and mouse models, and their possible clinical implications. We highlight how this cancer-related ribosome biogenesis, both at quantitative and qualitative levels, can lead to the synthesis of ribosomes favoring the translation of mRNAs encoding hyperproliferative and survival factors. We also discuss whether cancer-related ribosome biogenesis is a mere consequence of cancer progression or is a causal factor in CRC, and how altered ribosome biogenesis pathways can represent effective targets to kill CRC cells. The association between exacerbated CRC cell growth and alteration of specific steps of ribosome biogenesis is highlighted as a key driver of tumorigenesis, providing promising perspectives for the implementation of predictive biomarkers and the development of new therapeutic drugs.
Collapse
Affiliation(s)
- Sophie Nait Slimane
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Virginie Marcel
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Tanguy Fenouil
- Institute of Pathology EST, Hospices Civils de Lyon, Site-Est Groupement Hospitalier- Est, 69677 Bron, France;
| | - Frédéric Catez
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Jean-Christophe Saurin
- Gastroenterology and Genetic Department, Edouard Herriot Hospital, Hospices Civils de Lyon, 69008 Lyon, France;
| | - Philippe Bouvet
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Jean-Jacques Diaz
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Hichem C. Mertani
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| |
Collapse
|
6
|
Haupt S, Caramia F, Herschtal A, Soussi T, Lozano G, Chen H, Liang H, Speed TP, Haupt Y. Identification of cancer sex-disparity in the functional integrity of p53 and its X chromosome network. Nat Commun 2019; 10:5385. [PMID: 31772231 PMCID: PMC6879765 DOI: 10.1038/s41467-019-13266-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/31/2019] [Indexed: 12/12/2022] Open
Abstract
The disproportionately high prevalence of male cancer is poorly understood. We tested for sex-disparity in the functional integrity of the major tumor suppressor p53 in sporadic cancers. Our bioinformatics analyses expose three novel levels of p53 impact on sex-disparity in 12 non-reproductive cancer types. First, TP53 mutation is more frequent in these cancers among US males than females, with poorest survival correlating with its mutation. Second, numerous X-linked genes are associated with p53, including vital genomic regulators. Males are at unique risk from alterations of their single copies of these genes. High expression of X-linked negative regulators of p53 in wild-type TP53 cancers corresponds with reduced survival. Third, females exhibit an exceptional incidence of non-expressed mutations among p53-associated X-linked genes. Our data indicate that poor survival in males is contributed by high frequencies of TP53 mutations and an inability to shield against deregulated X-linked genes that engage in p53 networks.
Collapse
Affiliation(s)
- Sue Haupt
- Tumor Suppression Laboratory, Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, Victoria, 3000, Australia. .,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, 3010, Australia.
| | - Franco Caramia
- Tumor Suppression Laboratory, Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, Victoria, 3000, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Alan Herschtal
- Department of Biometrics Novotech, Carlton, Victoria, 3053, Australia
| | - Thierry Soussi
- Department of Oncology-Pathology, Karolinska Institute, Cancer Center Karolinska, Solna, Sweden.,INSERM, U1138, Centre de Recherche des Cordeliers, Paris, France
| | - Guillermina Lozano
- The University of Texas, MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Hu Chen
- Graduate Program in Quantitative and Computational Biosciences, Baylor College of Medicine, Houston, TX, 77030, USA.,Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Han Liang
- Graduate Program in Quantitative and Computational Biosciences, Baylor College of Medicine, Houston, TX, 77030, USA.,Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Terence P Speed
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Ygal Haupt
- Tumor Suppression Laboratory, Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, Victoria, 3000, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, 3010, Australia.,Department of Clinical Pathology, University of Melbourne, Parkville, Victoria, 3010, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| |
Collapse
|
7
|
Gaviraghi M, Vivori C, Tonon G. How Cancer Exploits Ribosomal RNA Biogenesis: A Journey beyond the Boundaries of rRNA Transcription. Cells 2019; 8:cells8091098. [PMID: 31533350 PMCID: PMC6769540 DOI: 10.3390/cells8091098] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/13/2019] [Accepted: 09/15/2019] [Indexed: 02/06/2023] Open
Abstract
The generation of new ribosomes is a coordinated process essential to sustain cell growth. As such, it is tightly regulated according to cell needs. As cancer cells require intense protein translation to ensure their enhanced growth rate, they exploit various mechanisms to boost ribosome biogenesis. In this review, we will summarize how oncogenes and tumor suppressors modulate the biosynthesis of the RNA component of ribosomes, starting from the description of well-characterized pathways that converge on ribosomal RNA transcription while including novel insights that reveal unexpected regulatory networks hacked by cancer cells to unleash ribosome production.
Collapse
Affiliation(s)
- Marco Gaviraghi
- Experimental Imaging Center; Ospedale San Raffaele, 20132 Milan, Italy.
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Claudia Vivori
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, 08003 Barcelona, Spain.
| | - Giovanni Tonon
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
- Center for Translational Genomics and Bioinformatics, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
| |
Collapse
|
8
|
Li KK, Mao CY, Zhang JG, Ma Q, Wang YJ, Liu XH, Bao T, Guo W. Overexpression of U three protein 14a (UTP14a) is associated with poor prognosis of esophageal squamous cell carcinoma. Thorac Cancer 2019; 10:2071-2080. [PMID: 31496055 PMCID: PMC6825924 DOI: 10.1111/1759-7714.13176] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/06/2019] [Accepted: 08/06/2019] [Indexed: 12/09/2022] Open
Abstract
Background Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive and lethal cancers lacking valid prognostic biomarkers. As an essential component of a large ribonucleoprotein complex, U Three Protein 14a (UTP14a) might play important roles in human tumorigenesis. However, the clinical significance and functions of UTP14a in ESCC still remain unclear. Methods From September 2009 to August 2015, 210 patients with ESCC of the thoracic esophagus underwent thoracoscopic esophagectomy in our institute. The corresponding 210 tissue samples and 30 cancer‐distant mucosa (CDM) samples were tested for UTP14a expression by immunohistochemical staining. The long‐term survival was analyzed by the Kaplan–Meier method and Cox proportional hazards regression analyses. CCK8, cell colony formation, cell cycle, apoptosis, cell invasion, and wound healing assays were carried out with ECA109 cells to evaluate the effects of UTP14a on ESCC in vitro. Results UTP14a was positively expressed in 88.1% (185/210) of the ESCC samples. UTP14a expression in ESCC was significantly higher than in CDM, as further confirmed by Western blot analysis. High expression of UTP14a in ESCC correlated significantly with tumor invasive depth (pT stage), which predicts poor disease‐free survival and disease‐specific survival, as indicated by the log‐rank test and Cox proportional hazards regression analysis. Additionally, our in vitro experiments further demonstrated that knockdown of UTP14a inhibits cell proliferation and invasion in ECA109 cells. Conclusions Our results suggest that UTP14a is aberrantly expressed in ESCC, plays a critical role in cancer progression and could be a potential prognosis predictor of ESCC.
Collapse
Affiliation(s)
- Kun-Kun Li
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Cheng-Yi Mao
- Department of Pathology, Daping Hospital, Army Medical University, Chongqing, China
| | - Jing-Ge Zhang
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Qiang Ma
- Department of Pathology, Daping Hospital, Army Medical University, Chongqing, China
| | - Ying-Jian Wang
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xue-Hai Liu
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Tao Bao
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Wei Guo
- Department of Thoracic Surgery, Daping Hospital, Army Medical University, Chongqing, China
| |
Collapse
|
9
|
Sayed S, Paszkowski-Rogacz M, Schmitt LT, Buchholz F. CRISPR/Cas9 as a tool to dissect cancer mutations. Methods 2019; 164-165:36-48. [PMID: 31078796 DOI: 10.1016/j.ymeth.2019.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/03/2019] [Accepted: 05/06/2019] [Indexed: 12/26/2022] Open
Abstract
The CRISPR/Cas9 system is transforming many biomedical disciplines, including cancer research. Through its flexible programmability and efficiency to induce DNA double strand breaks it has become straightforward to introduce cancer mutations into cells in vitro and/or in vivo. However, not all mutations contribute equally to tumorigenesis and distinguishing essential mutations for tumor growth and survival from biologically inert mutations is cumbersome. Here we present a method to screen for the functional relevance of mutations in high throughput in established cancer cell lines. We employ the CRISPR/Cas9 system to probe cancer vulnerabilities in a colorectal carcinoma cell line in an attempt to identify novel cancer driver mutations. We designed 100 high quality sgRNAs that are able to specifically cleave mutations present in the colorectal carcinoma cell line RKO. An all-in-one lentiviral library harboring these sgRNAs was then generated and used in a pooled screen to probe possible growth dependencies on these mutations. Genomic DNA at different time points were collected, the sgRNA cassettes were PCR amplified, purified and sgRNA counts were quantified by means of deep sequencing. The analysis revealed two sgRNAs targeting the same mutation (UTP14A: S99delS) to be depleted over time in RKO cells. Validation and characterization confirmed that the inactivation of this mutation impairs cell growth, nominating UTP14A: S99delS as a putative driver mutation in RKO cells. Overall, our approach demonstrates that the CRISPR/Cas9 system is a powerful tool to functionally dissect cancer mutations at large-scale.
Collapse
Affiliation(s)
- Shady Sayed
- Carl Gustav Carus Faculty of Medicine, UCC, Section Medical Systems Biology, TU Dresden, Germany; National Center for Tumor Diseases (NCT), University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Maciej Paszkowski-Rogacz
- Carl Gustav Carus Faculty of Medicine, UCC, Section Medical Systems Biology, TU Dresden, Germany
| | - Lukas Theo Schmitt
- Carl Gustav Carus Faculty of Medicine, UCC, Section Medical Systems Biology, TU Dresden, Germany
| | - Frank Buchholz
- Carl Gustav Carus Faculty of Medicine, UCC, Section Medical Systems Biology, TU Dresden, Germany; National Center for Tumor Diseases (NCT), University Hospital Carl Gustav Carus, TU Dresden, Germany; German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK) Partner Site Dresden, Germany; Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
| |
Collapse
|
10
|
Ren P, Sun X, Zhang C, Wang L, Xing B, Du X. Human UTP14a promotes angiogenesis through upregulating PDGFA expression in colorectal cancer. Biochem Biophys Res Commun 2019; 512:871-876. [DOI: 10.1016/j.bbrc.2019.03.142] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 03/21/2019] [Indexed: 02/07/2023]
|
11
|
Gennaro VJ, Wedegaertner H, McMahon SB. Interaction between the BAG1S isoform and HSP70 mediates the stability of anti-apoptotic proteins and the survival of osteosarcoma cells expressing oncogenic MYC. BMC Cancer 2019; 19:258. [PMID: 30902071 PMCID: PMC6429775 DOI: 10.1186/s12885-019-5454-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 03/12/2019] [Indexed: 02/07/2023] Open
Abstract
Background The oncoprotein MYC has the dual capacity to drive cell cycle progression or induce apoptosis, depending on the cellular context. BAG1 was previously identified as a transcriptional target of MYC that functions as a critical determinant of this cell fate decision. The BAG1 protein is expressed as multiple isoforms, each having an array of distinct biochemical functions; however, the specific effector function of BAG1 that directs MYC-dependent cell survival has not been defined. Methods In our studies the human osteosarcoma line U2OS expressing a conditional MYC-ER allele was used to induce oncogenic levels of MYC. We interrogated MYC-driven survival processes by modifying BAG1 protein expression. The function of the separate BAG1 isoforms was investigated by depleting cells of endogenous BAG1 and reintroducing the distinct isoforms. Flow cytometry and immunoblot assays were performed to analyze the effect of specific BAG1 isoforms on MYC-dependent apoptosis. These experiments were repeated to determine the role of the HSP70 chaperone complex in BAG1 survival processes. Finally, a proteomic approach was used to identify a set of specific pro-survival proteins controlled by the HSP70/BAG1 complex. Results Loss of BAG1 resulted in robust MYC-induced apoptosis. Expression of the larger isoforms of BAG1, BAG1L and BAG1M, were insufficient to rescue survival in cells with oncogenic levels of MYC. Alternatively, reintroduction of BAG1S significantly reduced the level of apoptosis. Manipulation of the BAG1S interaction with HSP70 revealed that BAG1S provides its pro-survival function by serving as a cofactor for the HSP70 chaperone complex. Via a proteomic approach we identified and classified a set of pro-survival proteins controlled by this HSP70/BAG1 chaperone complex that contribute to the BAG1 anti-apoptotic phenotype. Conclusions The small isoform of BAG1, BAG1S, in cooperation with the HSP70 chaperone complex, selectively mediates cell survival in MYC overexpressing tumor cells. We identified a set of specific pro-survival clients controlled by the HSP70/BAG1S chaperone complex. These clients define new nodes that could be therapeutically targeted to disrupt the survival of tumor cells driven by MYC activation. With MYC overexpression occurring in most human cancers, this introduces new strategies for cancer treatment. Electronic supplementary material The online version of this article (10.1186/s12885-019-5454-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Victoria J Gennaro
- Department of Biochemistry and Molecular Biology Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Helen Wedegaertner
- Department of Biochemistry and Molecular Biology Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Steven B McMahon
- Department of Biochemistry and Molecular Biology Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.
| |
Collapse
|
12
|
Zhang CF, Liu Y, Lu M, DU XJ. [Expression of hUTP14a in non-small cell lung cancer]. JOURNAL OF PEKING UNIVERSITY. HEALTH SCIENCES 2019; 51:145-150. [PMID: 30773559 DOI: 10.19723/j.issn.1671-167x.2019.01.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Human U three protein 14a (hUTP14a) facilitates tumorigenesis through promoting p53 and Rb degradation as well as enhancing c-Myc oncogenic activity. Moreover, hUTP14a expression is up-regulated in human hepatocellular cancer and colorectal cancer tissues. In this study, the expression of hUTP14a in non-small cell lung cancer (NSCLC) tissues was evaluated by immunohistochemistry staining (IHC). The relationship between hUTP14a expression levels and the clinical characteristics of the NSCLC patients were analyzed. METHODS Lung cancer tissues and the adjacent non-cancerous tissues were collected from 123 cases of NSCLC patients including 53 cases of squamous cell carcinoma (SCC) and 70 cases of adenocarcinoma (ADC), who had accepted surgical resection at Peking University Third Hospital from May 2003 to April 2006. The expression level of hUTP14a was determined by IHC in human NSCLC tissues and the adjacent non-cancerous tissues. The associations between hUTP14a expression and the clinical pathological variables including gender, age, tumor size, histological type, differentiation degree and clinical pathological stage were analyzed using the Pearson's χ2 test. RESULTS The expression rate of hUTP14a in NSCLC tissues was significantly higher than that in the non-cancerous tissues (37.4% vs. 0, P<0.001). The expressions of hUTP14a in lung ADC and SCC were 48.6% and 20.6%, respectively. The expression rate of hUTP14a in both lung ADC and SCC was significantly higher than that in the adjacent non-cancerous tissues (P<0.001). In addition, the expression rate of hUTP14a in lung ADC was significantly higher than that in SCC (χ2=8.66, P=0.003). Furthermore, the expression rate of hUTP14a in the late pTNM stage of SCC was significantly higher than that in the early pTNM stage of SCC while hUTP14a expression level was not associated with pTNM stage of ADC. No correlation was found between hUTP14a expression and the other clinical pathologic features of the patients. CONCLUSION Expression of hUTP14a was up-regulated in NSCLC tissues and was correlated with pTNM stage of SCC, suggesting that hUTP14a might possess a potential as a candidate marker for the early diagnosis screening of NSCLC.
Collapse
Affiliation(s)
- C F Zhang
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China
| | - Y Liu
- Peking University Centre of Medical and Health Analysis, Beijing 100191, China
| | - M Lu
- Department of Pathology, Peking University School of Basic Medical Sciences, Beijing 100191, China
| | - X J DU
- Department of Cell Biology, Peking University School of Basic Medical Sciences, Beijing 100191, China
| |
Collapse
|
13
|
Zhang J, Ren P, Xu D, Liu X, Liu Z, Zhang C, Li Y, Wang L, Du X, Xing B. Human UTP14a promotes colorectal cancer progression by forming a positive regulation loop with c-Myc. Cancer Lett 2019; 440-441:106-115. [DOI: 10.1016/j.canlet.2018.10.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 09/30/2018] [Accepted: 10/08/2018] [Indexed: 01/08/2023]
|
14
|
Liu H, Wang J, Liu Y, Hu L, Zhang C, Xing B, Du X. Human U3 protein14a is a novel type ubiquitin ligase that binds RB and promotes RB degradation depending on a leucine-rich region. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1611-1620. [DOI: 10.1016/j.bbamcr.2018.08.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 08/22/2018] [Accepted: 08/23/2018] [Indexed: 11/16/2022]
|
15
|
Ma T, Lu C, Guo Y, Zhang C, Du X. Human U3 protein 14a plays an anti-apoptotic role in cancer cells. Biol Chem 2017; 398:1247-1257. [PMID: 28672776 DOI: 10.1515/hsz-2017-0121] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/21/2017] [Indexed: 01/21/2023]
Abstract
Human U three protein 14a (hUTP14a) binds p53 and promotes p53 degradation. Here, we report that hUTP14a plays an anti-apoptotic role in tumor cells through a p53-independent pathway. Knockdown of hUTP14a activated the intrinsic pathway of apoptosis and sensitized tumor cells to chemotherapeutic drug-induced apoptosis. In addition, the protein level of hUTP14a decreased upon chemotherapeutic drug- or irradiation-induced apoptosis. Importantly, the decrease of hUTP14a during induced apoptosis was not blocked by pan-caspase inhibitor z-VAD-FMK, indicating that the down-regulation of hUTP14a is an upstream event in apoptosis. Furthermore, ectopically expressed hUTP14a protected tumor cells from chemotherapeutic drug-induced apoptosis. In summary, our data showed that hUTP14a protected tumor cells from chemotherapeutic drug-induced apoptosis and thus might possess a potential as a target for anti-tumor therapy.
Collapse
|
16
|
Memet I, Doebele C, Sloan KE, Bohnsack MT. The G-patch protein NF-κB-repressing factor mediates the recruitment of the exonuclease XRN2 and activation of the RNA helicase DHX15 in human ribosome biogenesis. Nucleic Acids Res 2017; 45:5359-5374. [PMID: 28115624 PMCID: PMC5435916 DOI: 10.1093/nar/gkx013] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/04/2017] [Indexed: 01/05/2023] Open
Abstract
In eukaryotes, the synthesis of ribosomal subunits, which involves the maturation of the ribosomal (r)RNAs and assembly of ribosomal proteins, requires the co-ordinated action of a plethora of ribosome biogenesis factors. Many of these cofactors remain to be characterized in human cells. Here, we demonstrate that the human G-patch protein NF-κB-repressing factor (NKRF) forms a pre-ribosomal subcomplex with the DEAH-box RNA helicase DHX15 and the 5΄-3΄ exonuclease XRN2. Using UV crosslinking and analysis of cDNA (CRAC), we reveal that NKRF binds to the transcribed spacer regions of the pre-rRNA transcript. Consistent with this, we find that depletion of NKRF, XRN2 or DHX15 impairs an early pre-rRNA cleavage step (A’). The catalytic activity of DHX15, which we demonstrate is stimulated by NKRF functioning as a cofactor, is required for efficient A’ cleavage, suggesting that a structural remodelling event may facilitate processing at this site. In addition, we show that depletion of NKRF or XRN2 also leads to the accumulation of excised pre-rRNA spacer fragments and that NKRF is essential for recruitment of the exonuclease to nucleolar pre-ribosomal complexes. Our findings therefore reveal a novel pre-ribosomal subcomplex that plays distinct roles in the processing of pre-rRNAs and the turnover of excised spacer fragments.
Collapse
Affiliation(s)
- Indira Memet
- Institute for Molecular Biology, University Medical Center Göttingen, Georg-August-University, 37073 Göttingen, Germany
| | - Carmen Doebele
- Institute for Molecular Biology, University Medical Center Göttingen, Georg-August-University, 37073 Göttingen, Germany
| | - Katherine E Sloan
- Institute for Molecular Biology, University Medical Center Göttingen, Georg-August-University, 37073 Göttingen, Germany
| | - Markus T Bohnsack
- Institute for Molecular Biology, University Medical Center Göttingen, Georg-August-University, 37073 Göttingen, Germany.,Göttingen Centre for Molecular Biosciences, Georg-August-University, 37073 Göttingen, Germany
| |
Collapse
|
17
|
Zhang JY, Xu D, Liu ZZ, Li Y, Wang LJ, Xing BC. Human U Three Protein 14a Expression is Increased in Hepatocellular Carcinoma and Associated with Poor Prognosis. Chin Med J (Engl) 2017; 130:470-476. [PMID: 28218222 PMCID: PMC5324385 DOI: 10.4103/0366-6999.199839] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Background: Human U three protein 14a (hUTP14a) promotes p53 degradation. Moreover, hUTP14a expression is upregulated in several types of tumors. However, the expression pattern of hUTP14a in hepatocellular carcinoma (HCC) remains unknown. The aim of this study was to investigate hUTP14a expression and its prognostic value in HCC. Methods: The hUTP14a expression was evaluated using immunohistochemistry (IHC) in HCC tissue specimens. The correlations between hUTP14a expression and clinicopathological variables were analyzed. The Kaplan-Meier method was used to analyze the association between hUTP14a expression and survival. Independent prognostic factors associated with overall survival (OS) and disease-free survival (DFS) were analyzed using the Cox proportional-hazards regression model. Results: The IHC data revealed that the hUTP14a positivity rate in HCC tissue specimens was significantly higher than that in nontumorous tissue specimens (89.9% vs. 72.7%, P < 0.05). The hUTP14a expression was detected in both the nucleolus and the cytoplasm. The positivity rate of nucleolar hUTP14a expression in HCC tissue specimens was higher than that in the nontumorous tissue specimens (29.3% vs. 10.1%, P < 0.05). No significant difference was found between HCC and nontumorous tissue specimens of cytoplasmic hUTP14a expression (60.6% vs. 62.6%, P > 0.05). In addition, no significant correlation was found between nucleolar hUTP14a expression and other clinicopathological variables. The 5-year OS and DFS rates in patients with positive nucleolar hUTP14a expression were significantly lower than those in patients with negative hUTP14a expression (P = 0.004 for OS, P = 0.003 for DFS). Multivariate analysis showed that nucleolar hUTP14a expression was an independent prognostic factor for OS (P = 0.004) and DFS (P < 0.001). Conclusions: The positivity rate of hUTP14a expression was significantly higher in HCC specimens. Positive expression of nucleolar hUTP14a might act as a novel prognostic predictor for patients with HCC.
Collapse
Affiliation(s)
- Jing-Yi Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Da Xu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Zhen-Zhen Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Yuan Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Li-Jun Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Bao-Cai Xing
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Hepatopancreatobiliary Surgery Department I, Peking University Cancer Hospital and Institute, Beijing 100142, China
| |
Collapse
|
18
|
Larsen DH, Stucki M. Nucleolar responses to DNA double-strand breaks. Nucleic Acids Res 2015; 44:538-44. [PMID: 26615196 PMCID: PMC4737151 DOI: 10.1093/nar/gkv1312] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/09/2015] [Indexed: 11/25/2022] Open
Abstract
Maintenance of cellular homeostasis is key to prevent transformation and disease. The cellular response to DNA double-strand breaks, primarily orchestrated by the ATM/ATR kinases is one of many mechanisms that serve to uphold genome stability and homeostasis. Upon detection of double-strand breaks (DSBs), several signaling cascades are activated to halt cell cycle progression and initiate repair. Furthermore, the DNA damage response (DDR) controls cellular processes such as transcription, splicing and metabolism. Recent studies have uncovered aspects of how the DDR operates within nucleoli. It appears that the DDR controls transcription in the nucleoli, not only when DNA breaks occur in the rDNA repeats, but also when a nuclear DDR is activated. In addition, we have gained first insights into how repair of DSBs is organized in the nucleolus. Collectively, these recent studies provide a more comprehensive picture of how the DDR regulates basic cellular functions to maintain cellular homeostasis. In this review we will summarize recent findings and discuss their implications for our understanding of how the DDR regulates transcription and repair in the nucleolus.
Collapse
Affiliation(s)
- Dorthe Helena Larsen
- Danish Cancer Society Research Center, Strandboulevarden 49, 2100 Copenhagen, Denmark
| | - Manuel Stucki
- Department of Gynecology, University of Zurich, Wagistrasse 14, CH-8952 Schlieren, Switzerland
| |
Collapse
|
19
|
Wang Y, Zheng Z, Zhang J, Wang Y, Kong R, Liu J, Zhang Y, Deng H, Du X, Ke Y. A Novel Retinoblastoma Protein (RB) E3 Ubiquitin Ligase (NRBE3) Promotes RB Degradation and Is Transcriptionally Regulated by E2F1 Transcription Factor. J Biol Chem 2015; 290:28200-28213. [PMID: 26442585 DOI: 10.1074/jbc.m115.655597] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 12/25/2022] Open
Abstract
Retinoblastoma protein (RB) plays critical roles in tumor suppression and is degraded through the proteasomal pathway. However, E3 ubiquitin ligases responsible for proteasome-mediated degradation of RB are largely unknown. Here we characterize a novel RB E3 ubiquitin ligase (NRBE3) that binds RB and promotes RB degradation. NRBE3 contains an LXCXE motif and bound RB in vitro. NRBE3 interacted with RB in cells when proteasome activity was inhibited. NRBE3 promoted RB ubiquitination and degradation via the ubiquitin-proteasome pathway. Importantly, purified NRBE3 ubiquitinated recombinant RB in vitro, and a U-box was identified as essential for its E3 activity. Surprisingly, NRBE3 was transcriptionally activated by E2F1/DP1. Consequently, NRBE3 affected the cell cycle by promoting G1/S transition. Moreover, NRBE3 was up-regulated in breast cancer tissues. Taken together, we identified NRBE3 as a novel ubiquitin E3 ligase for RB that might play a role as a potential oncoprotein in human cancers.
Collapse
Affiliation(s)
- Yingshuang Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Zongfang Zheng
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Jingyi Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education)
| | - You Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Ruirui Kong
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Jiangying Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Ying Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| | - Hongkui Deng
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Xiaojuan Du
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
| | - Yang Ke
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China
| |
Collapse
|
20
|
Yelick PC, Trainor PA. Ribosomopathies: Global process, tissue specific defects. Rare Dis 2015; 3:e1025185. [PMID: 26442198 PMCID: PMC4590025 DOI: 10.1080/21675511.2015.1025185] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/18/2015] [Accepted: 02/26/2015] [Indexed: 01/01/2023] Open
Abstract
Disruptions in ribosomal biogenesis would be expected to have global and in fact lethal effects on a developing organism. However, mutations in ribosomal protein genes have been shown in to exhibit tissue specific defects. This seemingly contradictory finding - that globally expressed genes thought to play fundamental housekeeping functions can in fact exhibit tissue and cell type specific functions - provides new insight into roles for ribosomes, the protein translational machinery of the cell, in regulating normal development and disease. Furthermore it illustrates the surprisingly dynamic nature of processes regulating cell type specific protein translation. In this review, we discuss our current knowledge of a variety of ribosomal protein mutations associated with human disease, and models to better understand the molecular mechanisms associated with each. We use specific examples to emphasize both the similarities and differences between the effects of various human ribosomal protein mutations. Finally, we discuss areas of future study that are needed to further our understanding of the role of ribosome biogenesis in normal development, and possible approaches that can be used to treat debilitating ribosomopathy diseases.
Collapse
Affiliation(s)
| | - Paul A Trainor
- Stowers Institute ; Kansas City, MO USA ; University of Kansas Medical Center ; Kansas City, KS USA
| |
Collapse
|
21
|
Cellular STAT3 functions via PCBP2 to restrain Epstein-Barr Virus lytic activation in B lymphocytes. J Virol 2015; 89:5002-11. [PMID: 25717101 DOI: 10.1128/jvi.00121-15] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 02/13/2015] [Indexed: 12/23/2022] Open
Abstract
UNLABELLED A major hurdle to killing Epstein-Barr virus (EBV)-infected tumor cells using oncolytic therapy is the presence of a substantial fraction of EBV-infected cells that does not support the lytic phase of EBV despite exposure to lytic cycle-promoting agents. To determine the mechanism(s) underlying this refractory state, we developed a strategy to separate lytic from refractory EBV-positive (EBV(+)) cells. By examining the cellular transcriptome in separated cells, we previously discovered that high levels of host STAT3 (signal transducer and activator of transcription 3) curtail the susceptibility of latently infected cells to lytic cycle activation signals. The goals of the present study were 2-fold: (i) to determine the mechanism of STAT3-mediated resistance to lytic activation and (ii) to exploit our findings to enhance susceptibility to lytic activation. We therefore analyzed our microarray data set, cellular proteomes of separated lytic and refractory cells, and a publically available STAT3 chromatin immunoprecipitation sequencing (ChIP-Seq) data set to identify cellular PCBP2 [poly(C)-binding protein 2], an RNA-binding protein, as a transcriptional target of STAT3 in refractory cells. Using Burkitt lymphoma cells and EBV(+) cell lines from patients with hypomorphic STAT3 mutations, we demonstrate that single cells expressing high levels of PCBP2 are refractory to spontaneous and induced EBV lytic activation, STAT3 functions via cellular PCBP2 to regulate lytic susceptibility, and suppression of PCBP2 levels is sufficient to increase the number of EBV lytic cells. We expect that these findings and the genome-wide resources that they provide will accelerate our understanding of a longstanding mystery in EBV biology and guide efforts to improve oncolytic therapy for EBV-associated cancers. IMPORTANCE Most humans are infected with Epstein-Barr virus (EBV), a cancer-causing virus. While EBV generally persists silently in B lymphocytes, periodic lytic (re)activation of latent virus is central to its life cycle and to most EBV-related diseases. However, a substantial fraction of EBV-infected B cells and tumor cells in a population is refractory to lytic activation. This resistance to lytic activation directly and profoundly impacts viral persistence and the effectiveness of oncolytic therapy for EBV(+) cancers. To identify the mechanisms that underlie susceptibility to EBV lytic activation, we used host gene and protein expression profiling of separated lytic and refractory cells. We find that STAT3, a transcription factor overactive in many cancers, regulates PCBP2, a protein important in RNA biogenesis, to regulate susceptibility to lytic cycle activation signals. These findings advance our understanding of EBV persistence and provide important leads on devising methods to improve viral oncolytic therapies.
Collapse
|
22
|
Sondalle SB, Baserga SJ. Human diseases of the SSU processome. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1842:758-64. [PMID: 24240090 PMCID: PMC4058823 DOI: 10.1016/j.bbadis.2013.11.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 10/31/2013] [Accepted: 11/05/2013] [Indexed: 12/18/2022]
Abstract
Ribosomes are the cellular machines responsible for protein synthesis. Ribosome biogenesis, the production of ribosomes, is a complex process involving pre-ribosomal RNA (rRNA) cleavages and modifications as well as ribosomal protein assembly around the rRNAs to create the functional ribosome. The small subunit (SSU) processome is a large ribonucleoprotein (RNP) in eukaryotes required for the assembly of the SSU of the ribosome as well as for the maturation of the 18S rRNA. Despite the fundamental nature of the SSU processome to the survival of any eukaryotic cell, mutations in SSU processome components have been implicated in human diseases. Three SSU processome components and their related human diseases will be explored in this review: hUTP4/Cirhin, implicated in North American Indian childhood cirrhosis (NAIC); UTP14, implicated in infertility, ovarian cancer, and scleroderma; and EMG1, implicated in Bowen-Conradi syndrome (BCS). Diseases with suggestive, though inconclusive, evidence for the involvement of the SSU processome in their pathogenesis are also discussed, including a novel putative ribosomopathy. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.
Collapse
Affiliation(s)
- Samuel B Sondalle
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - Susan J Baserga
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA.
| |
Collapse
|
23
|
Zhang J, Guo Y, Du X, Xing B. Does not hUTP14a promoter form a regulation feedback loop with P53? Chin J Cancer Res 2014; 26:159-65. [PMID: 24826056 DOI: 10.3978/j.issn.1000-9604.2014.03.03] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/10/2014] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE We previously found that hUTP14a binds P53 and promotes P53 degradation. However, if hUTP14a is a downstream gene of P53 remains to be determined. This study aimed to identify the promoter of hUTP14a and investigate if hUTP14a is regulated by P53. METHODS The hUTP14a promoter region was cloned into pGL3-Basic-luciferase reporter plasmid to get pGL3-hUTP14a-luc. The reporter plasmid was transfected into 293T cells and luciferase activity was evaluated by the Dual-Luciferase Reporter Assay System. Putative transcription factors were identified through searching MatInspector Professional and Algorismica i Genetica databases. Either pGL3-hUTP14a-luc or p21 promoter reporter plasmid was co-transfected with increasing dose of p53 plasmid, and luciferase activity was evaluated. A series of deletion constructs of pGL3-hUTP14a-luc were constructed and minimal promoter region of hUTP14a was determined. Differences of the luciferase activities between different groups were assessed by statistical analysis. RESULTS The hUTP14a gene promoter reporter construct was correctly cloned and was demonstrated to possess promoter activity. The transcription of hUTP14a was not regulated by P53. The minimal promoter region of hUTP14a gene is located between -203 to -100 of the transcription initiation site. CONCLUSION Unlike other P53-interacting proteins such as MDM2, Pirh2 and Cop I which promote P53 degradation and whose transcriptions are regulated by P53, does not hUTP14a transcription form a regulation feedback loop with P53.
Collapse
Affiliation(s)
- Jingyi Zhang
- 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Hepatic, Biliary & Pancreatic Surgery I, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China
| | - Yafei Guo
- 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Hepatic, Biliary & Pancreatic Surgery I, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China
| | - Xiaojuan Du
- 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Hepatic, Biliary & Pancreatic Surgery I, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China
| | - Baocai Xing
- 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Hepatic, Biliary & Pancreatic Surgery I, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 Department of Cell Biology, Peking University Health Science Center, Beijing 100191, China
| |
Collapse
|
24
|
Srivastava A, Ahamad J, Ray AK, Kaur D, Bhattacharya A, Bhattacharya S. Analysis of U3 snoRNA and small subunit processome components in the parasitic protist Entamoeba histolytica. Mol Biochem Parasitol 2014; 193:82-92. [PMID: 24631428 DOI: 10.1016/j.molbiopara.2014.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 02/27/2014] [Accepted: 03/01/2014] [Indexed: 10/25/2022]
Abstract
In the early branching parasitic protist Entamoeba histolytica, pre-rRNA synthesis continues when cells are subjected to growth stress, but processing slows down and unprocessed pre-rRNA accumulates. To gain insight into the regulatory mechanisms leading to accumulation, it is necessary to define the pre-rRNA processing machinery in E. histolytica. We searched the E. histolytica genome sequence for homologs of the SSU processome, which contains the U3snoRNA, and 72 proteins in yeast. We could identify 57 of the proteins with high confidence. Of the rest, 6 were absent in human, and 4 were non-essential in yeast. The remaining 5 were absent in other parasite genomes as well. Analysis of U3snoRNA showed that the E. histolytica U3snoRNA adopted the same conserved secondary structure as seen in yeast and human. The predicted structure was verified by chemical modification followed by primer extension (SHAPE). Further we showed that the predicted interactions of Eh_U3snoRNA boxes A and A' with pre-18S rRNA were highly conserved both in position and sequence. The predicted interactions of 5'-hinge and 3'-hinge sequences of Eh_U3 snoRNA with the 5'-ETS sequences were conserved in position but not in sequence. Transcription of selected genes of SSU processome was tested by northern analysis, and transcripts of predicted sizes were obtained. During serum starvation, when unprocessed pre-RNA accumulated, the transcript levels of some of these genes declined. This is the first report on pre-rRNA processing machinery in E. histolytica, and shows that the components are well conserved with respect to yeast and human.
Collapse
Affiliation(s)
- Ankita Srivastava
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Jamaluddin Ahamad
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Ashwini Kumar Ray
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Devinder Kaur
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| |
Collapse
|
25
|
Crepaldi CR, Vitale PAM, Tesch AC, Laure HJ, Rosa JC, de Cerqueira César M. Application of 2D BN/SDS-PAGE coupled with mass spectrometry for identification of VDAC-associated protein complexes related to mitochondrial binding sites for type I brain hexokinase. Mitochondrion 2013; 13:823-30. [PMID: 23719229 DOI: 10.1016/j.mito.2013.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 02/27/2013] [Accepted: 05/14/2013] [Indexed: 11/25/2022]
Abstract
Two types of binding sites for hexokinase, designated as Type A or Type B sites, have been shown to coexist on brain mitochondria. The ratio of these sites varies between species. HK1 attaches by reversibly binding to the voltage dependent anion channel (VDAC). Regarding the nature of hexokinase binding sites, we investigated if it was linked to distinct VDAC interactomes. We approached this question by 2D BN/SDS-PAGE of mitochondria, followed by mass spectrometry. Our results are consistent with the possibility that the ratio of Type A/Type B sites is due to differential VDAC interactions in bovine and rat neuronal cells.
Collapse
Affiliation(s)
- Carla Rossini Crepaldi
- Department of Basic Sciences, School of Animal Science and Food Engineering, University of São Paulo, Pirassununga, Brazil
| | | | | | | | | | | |
Collapse
|
26
|
Small nucleolar RNA expression profiling identifies potential prognostic markers in peripheral T-cell lymphoma. Blood 2012; 120:3997-4005. [PMID: 22990019 DOI: 10.1182/blood-2012-06-438135] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Peripheral T-cell lymphoma (PTCL) is a rare, heterogeneous type of non-Hodgkin lymphoma (NHL) that, in general, is associated with a poor clinical outcome. Therefore, a current major challenge is the discovery of new prognostic tools for this disease. In the present study, a cohort of 122 patients with PTCL was collected from a multicentric T-cell lymphoma consortium (TENOMIC). We analyzed the expression of 80 small nucleolar RNAs (snoRNAs) using high-throughput quantitative PCR. We demonstrate that snoRNA expression analysis may be useful in both the diagnosis of some subtypes of PTCL and the prognostication of both PTCL-not otherwise specified (PTCL-NOS; n = 26) and angio-immunoblastic T-cell lymphoma (AITL; n = 46) patients treated with chemotherapy. Like miRNAs, snoRNAs are globally down-regulated in tumor cells compared with their normal counterparts. In the present study, the snoRNA signature was robust enough to differentiate anaplastic large cell lymphoma (n = 32) from other PTCLs. For PTCL-NOS and AITL, we obtained 2 distinct prognostic signatures with a reduced set of 3 genes. Of particular interest was the prognostic value of HBII-239 snoRNA, which was significantly over-expressed in cases of AITL and PTCL-NOS that had favorable outcomes. Our results suggest that snoRNA expression profiles may have a diagnostic and prognostic significance for PTCL, offering new tools for patient care and follow-up.
Collapse
|
27
|
Li SM, Valo Z, Wang J, Gao H, Bowers CW, Singer-Sam J. Transcriptome-wide survey of mouse CNS-derived cells reveals monoallelic expression within novel gene families. PLoS One 2012; 7:e31751. [PMID: 22384067 PMCID: PMC3285176 DOI: 10.1371/journal.pone.0031751] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 01/12/2012] [Indexed: 01/08/2023] Open
Abstract
Monoallelic expression is an integral component of regulation of a number of essential genes and gene families. To probe for allele-specific expression in cells of CNS origin, we used next-generation sequencing (RNA-seq) to analyze four clonal neural stem cell (NSC) lines derived from Mus musculus C57BL/6 (B6)×Mus musculus molossinus (JF1) adult female mice. We established a JF1 cSNP library, then ascertained transcriptome-wide expression from B6 vs. JF1 alleles in the NSC lines. Validating the assay, we found that 262 of 268 X-linked genes evaluable in at least one cell line showed monoallelic expression (at least 85% expression of the predominant allele, p-value<0.05). For autosomal genes 170 of 7,198 genes (2.4% of the total) showed monoallelic expression in at least 2 evaluable cell lines. The group included eight known imprinted genes with the expected pattern of allele-specific expression. Among the other autosomal genes with monoallelic expression were five members of the glutathione transferase gene superfamily, which processes xenobiotic compounds as well as carcinogens and cancer therapeutic agents. Monoallelic expression within this superfamily thus may play a functional role in the response to diverse and potentially lethal exogenous factors, as is the case for the immunoglobulin and olfactory receptor superfamilies. Other genes and gene families showing monoallelic expression include the annexin gene family and the Thy1 gene, both linked to inflammation and cancer, as well as genes linked to alcohol dependence (Gabrg1) and epilepsy (Kcnma1). The annotated set of genes will provide a resource for investigation of mechanisms underlying certain cases of these and other major disorders.
Collapse
Affiliation(s)
- Sierra M. Li
- Division of Biostatistics, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Zuzana Valo
- Division of Biology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Jinhui Wang
- Division of Biology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Hanlin Gao
- Division of Biology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Chauncey W. Bowers
- Division of Computational Biology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Judith Singer-Sam
- Division of Biology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
- * E-mail:
| |
Collapse
|
28
|
Wu J, Zhang Y, Wang Y, Kong R, Hu L, Schuele R, Du X, Ke Y. Transcriptional repressor NIR functions in the ribosome RNA processing of both 40S and 60S subunits. PLoS One 2012; 7:e31692. [PMID: 22363708 PMCID: PMC3282729 DOI: 10.1371/journal.pone.0031692] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 01/17/2012] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND NIR was identified as an inhibitor of histone acetyltransferase and it represses transcriptional activation of p53. NIR is predominantly localized in the nucleolus and known as Noc2p, which is involved in the maturation of the 60S ribosomal subunit. However, how NIR functions in the nucleolus remains undetermined. In the nucleolus, a 47S ribosomal RNA precursor (pre-rRNA) is transcribed and processed to produce 18S, 5.8S and 28S rRNAs. The 18S rRNA is incorporated into the 40S ribosomal subunit, whereas the 28S and 5.8S rRNAs are incorporated into the 60S subunit. U3 small nucleolar RNA (snoRNA) directs 18S rRNA processing and U8 snoRNA mediates processing of 28S and 5.8 S rRNAs. Functional disruption of nucleolus often causes p53 activation to inhibit cell proliferation. METHODOLOGY/PRINCIPAL FINDINGS Western blotting showed that NIR is ubiquitously expressed in different human cell lines. Knock-down of NIR by siRNA led to inhibition of the 18S, 28S and 5.8S rRNAs evaluated by pulse-chase experiment. Pre-rRNA particles (pre-rRNPs) were fractionated from the nucleus by sucrose gradient centrifugation and analysis of the pre-RNPs components showed that NIR existed in the pre-RNPs of both the 60S and 40S subunits and co-fractionated with 32S and 12S pre-rRNAs in the 60S pre-rRNP. Protein-RNA binding experiments demonstrated that NIR is associated with the 32S pre-rRNA and U8 snoRNA. In addition, NIR bound U3 snoRNA. It is a novel finding that depletion of NIR did not affect p53 protein level but de-repressed acetylation of p53 and activated p21. CONCLUSIONS We provide the first evidence for a transcriptional repressor to function in the rRNA biogenesis of both the 40S and 60S subunits. Our findings also suggested that a nucleolar protein may alternatively signal to p53 by affecting the p53 modification rather than affecting p53 protein level.
Collapse
Affiliation(s)
- Jianguo Wu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing, China
| | - Ying Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing, China
| | - Yingshuang Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing, China
| | - Ruirui Kong
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing, China
| | - Lelin Hu
- Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Roland Schuele
- Medical Research Center, Freiburg University, Freiburg, Germany
| | - Xiaojuan Du
- Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Yang Ke
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Genetics Laboratory, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing, China
| |
Collapse
|
29
|
Rohozinski J, Edwards CL, Anderson ML. Does expression of the retrogene UTP14c in the ovary pre-dispose women to ovarian cancer? Med Hypotheses 2012; 78:446-9. [PMID: 22285623 DOI: 10.1016/j.mehy.2011.12.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 12/15/2011] [Accepted: 12/23/2011] [Indexed: 12/16/2022]
Abstract
It has been previously shown that the spermatogenesis associated retrogene, UTP14c, is expressed in over 50% of normal human ovaries and 80% of ovarian cancers. UTP14c is located on chromosome 13 as an intronless copy of the X-linked housekeeping gene, UTP14a. Like all spermatogenesis associated retrogenes, UTP14c is expressed in the testis and is essential for sperm production. It has no known role in the female and is not normally expressed in any cells or organs outside of the gonads. By comparison the protein encoded by UTP14a is found in all cell types and has a dual function. It is primarily involved in the biosynthesis of 18S ribosomal RNA in the nucleolus where it is a component of the U3 small nucleolar RNA associated protein complex. In addition, it down regulates TP53 in both the nucleus and cytoplasm by targeting it for proteolytic degradation. By analogy, we propose that the UTP14c peptide also targets TP53 for degradation. This in turn may prevent cells expressing UTP14c from entering apoptosis. The loss of TP53 in ovarian cells can also result in the down regulation of microRNA-145 (miR-145) expression. The loss of miR-145 can result in the activation of factors that promote oncogenesis and cellular pluripotency which in turn could lead to the development of ovarian cancer. We hypothesize that women, whose ovaries express UTP14c, are predisposed to ovarian cancer due to the disruption of protective signals that normally trigger TP53-mediated apoptosis and the dysregulation of genes that promote oncogenesis, such as c-Myc, that occurs when miR-145 synthesis is disrupted.
Collapse
Affiliation(s)
- Jan Rohozinski
- Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | | | | |
Collapse
|
30
|
Shetty G, Porter KL, Zhou W, Shao SH, Weng CCY, Meistrich ML. Androgen suppression-induced stimulation of spermatogonial differentiation in juvenile spermatogonial depletion mice acts by elevating the testicular temperature. Endocrinology 2011; 152:3504-14. [PMID: 21733828 PMCID: PMC3159784 DOI: 10.1210/en.2011-0251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Why both testosterone (T) suppression and cryptorchidism reverse the block in spermatogonial differentiation in adult mice homozygous for the juvenile spermatogonial depletion (jsd) mutation has been a conundrum. To resolve this conundrum, we analyzed interrelations between T suppression, testicular temperature, and spermatogonial differentiation and used in vitro techniques to separate the effects of the two treatments on the spermatogonial differentiation block in jsd mice. Temporal analysis revealed that surgical cryptorchidism rapidly stimulated spermatogonial differentiation whereas androgen ablation treatment produced a delayed and gradual differentiation. The androgen suppression caused scrotal shrinkage, significantly increasing the intrascrotal temperature. When serum T or intratesticular T (ITT) levels were modulated separately in GnRH antagonist-treated mice by exogenous delivery of T or LH, respectively, the inhibition of spermatogonial differentiation correlated with the serum T and not with ITT levels. Thus, the block must be caused by peripheral androgen action. When testicular explants from jsd mice were cultured in vitro at 32.5 C, spermatogonial differentiation was not observed, but at 37 C significant differentiation was evident. In contrast, addition of T to the culture medium did not block the stimulation of spermatogonial differentiation at 37 C, and androgen ablation with aminoglutethimide and hydroxyflutamide did not stimulate differentiation at 32.5 C, suggesting that T had no direct effect on spermatogonial differentiation in jsd mice. These data show that elevation of temperature directly overcomes the spermatogonial differentiation block in adult jsd mice and that T suppression acts indirectly in vivo by causing scrotal regression and thereby elevating the testicular temperature.
Collapse
Affiliation(s)
- Gunapala Shetty
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.
| | | | | | | | | | | |
Collapse
|