1
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Xia J, Zhao H, Edmondson JL, Koss B, Zhan F. Role of NEK2 in tumorigenesis and tumor progression. Trends Mol Med 2024:S1471-4914(24)00212-0. [PMID: 39181803 DOI: 10.1016/j.molmed.2024.07.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2024] [Revised: 07/15/2024] [Accepted: 07/30/2024] [Indexed: 08/27/2024]
Abstract
Never in mitosis A (NIMA)-related kinase 2 (NEK2) is a serine/threonine kinase found in the nucleus and cytoplasm throughout the cell cycle. NEK2 is overexpressed in many cancers and is a biomarker of poor prognosis. Factors contributing to NEK2 elevation in cancer cells include oncogenic transcription factors, decreased ubiquitination, DNA methylation, and the circular RNA (circRNA)/long noncoding RNA (lncRNA)-miRNA axis. NEK2 overexpression produces chromosomal instability and aneuploidy, thereby enhancing cancer progression and suppressing antitumor immunity, which highlights the prominence of NEK2 in tumorigenesis and tumor progression. Small-molecule inhibitors targeting NEK2 have demonstrated promising therapeutic potential in vitro and in vivo across various cancer types. This review outlines the regulatory mechanisms of NEK2 expression, emphasizes its functional roles in cancer initiation and progression, and highlights the anticancer properties of NEK2 inhibitors.
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Affiliation(s)
- Jiliang Xia
- Hunan Engineering Research Center for Early Diagnosis and Treatment of Liver Cancer, Cancer Research Institute, Hengyang Medical School, University of South China, Changshengxi Road 28, Hengyang, 421001, Hunan, China.
| | - Hongyan Zhao
- Hunan Engineering Research Center for Early Diagnosis and Treatment of Liver Cancer, Cancer Research Institute, Hengyang Medical School, University of South China, Changshengxi Road 28, Hengyang, 421001, Hunan, China
| | - Jacob L Edmondson
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Brian Koss
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Fenghuang Zhan
- Myeloma Center, Winthrop P. Rockefeller Cancer Institute, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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2
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Cesari E, Farini D, Medici V, Ehrmann I, Guerra M, Testa E, Naro C, Geloso MC, Pagliarini V, La Barbera L, D’Amelio M, Orsini T, Vecchioli SF, Tamagnone L, Fort P, Viscomi MT, Elliott DJ, Sette C. Differential expression of paralog RNA binding proteins establishes a dynamic splicing program required for normal cerebral cortex development. Nucleic Acids Res 2024; 52:4167-4184. [PMID: 38324473 PMCID: PMC11077083 DOI: 10.1093/nar/gkae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 01/17/2024] [Accepted: 01/25/2024] [Indexed: 02/09/2024] Open
Abstract
Sam68 and SLM2 are paralog RNA binding proteins (RBPs) expressed in the cerebral cortex and display similar splicing activities. However, their relative functions during cortical development are unknown. We found that these RBPs exhibit an opposite expression pattern during development. Sam68 expression declines postnatally while SLM2 increases after birth, and this developmental pattern is reinforced by hierarchical control of Sam68 expression by SLM2. Analysis of Sam68:Slm2 double knockout (Sam68:Slm2dko) mice revealed hundreds of exons that respond to joint depletion of these proteins. Moreover, parallel analysis of single and double knockout cortices indicated that exons regulated mainly by SLM2 are characterized by a dynamic splicing pattern during development, whereas Sam68-dependent exons are spliced at relatively constant rates. Dynamic splicing of SLM2-sensitive exons is completely suppressed in the Sam68:Slm2dko developing cortex. Sam68:Slm2dko mice die perinatally with defects in neurogenesis and in neuronal differentiation, and develop a hydrocephalus, consistent with splicing alterations in genes related to these biological processes. Thus, our study reveals that developmental control of separate Sam68 and Slm2 paralog genes encoding homologous RBPs enables the orchestration of a dynamic splicing program needed for brain development and viability, while ensuring a robust redundant mechanism that supports proper cortical development.
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Affiliation(s)
- Eleonora Cesari
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Donatella Farini
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
| | - Vanessa Medici
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Ingrid Ehrmann
- Newcastle University Centre for Cancer, Newcastle University Institute of Biosciences, Newcastle NE1 3BZ, UK
| | - Marika Guerra
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Erika Testa
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - Chiara Naro
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Maria Concetta Geloso
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Vittoria Pagliarini
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
| | - Livia La Barbera
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
| | - Marcello D’Amelio
- Fondazione Santa Lucia IRCCS, Via del Fosso di Fiorano, 64, 00143 Rome, Italy
- Università Campus Bio-Medico di Roma, Via Álvaro del Portillo, 21, 00128 Rome, Italy
| | - Tiziana Orsini
- Institute of Biochemistry and Cell Biology, National Research Council (IBBC/CNR), Monterotondo, 00015 Rome, Italy
| | - Stefano Farioli Vecchioli
- Institute of Biochemistry and Cell Biology, National Research Council (IBBC/CNR), Monterotondo, 00015 Rome, Italy
| | - Luca Tamagnone
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - Philippe Fort
- Centre de Recherche en Biologie Cellulaire de Montpellier, University of Montpellier, CNRS, 1919 Route de Mende, 34293 Montpellier Cedex 05, France
| | - Maria Teresa Viscomi
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
- Department of Life Science and Public Health, Section of Histology and Embryology, Catholic University of the Sacred Heart, Rome
| | - David J Elliott
- Newcastle University Centre for Cancer, Newcastle University Institute of Biosciences, Newcastle NE1 3BZ, UK
| | - Claudio Sette
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy
- Fondazione Policlinico Agostino Gemelli IRCCS, Largo Agostino Gemelli, 00168 Rome, Italy
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3
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Wang S, Sun H, Chen G, Wu C, Sun B, Lin J, Lin D, Zeng D, Lin B, Huang G, Lu X, Lin H, Liang Y. RNA-binding proteins in breast cancer: Biological implications and therapeutic opportunities. Crit Rev Oncol Hematol 2024; 195:104271. [PMID: 38272151 DOI: 10.1016/j.critrevonc.2024.104271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 01/05/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
RNA-binding proteins (RBPs) refer to a class of proteins that participate in alternative splicing, RNA stability, polyadenylation, localization and translation of RNAs, thus regulating gene expression in post-transcriptional manner. Dysregulation of RNA-RBP interaction contributes to various diseases, including cancer. In breast cancer, disorders in RBP expression and function influence the biological characteristics of tumor cells. Targeting RBPs has fostered the development of innovative therapies for breast cancer. However, the RBP-related mechanisms in breast cancer are not completely clear. In this review, we summarize the regulatory mechanisms of RBPs and their signaling crosstalk in breast cancer. Specifically, we emphasize the potential of certain RBPs as prognostic factors due to their effects on proliferation, invasion, apoptosis, and therapy resistance of breast cancer cells. Most importantly, we present a comprehensive overview of the latest RBP-related therapeutic strategies and novel therapeutic targets that have proven to be useful in the treatment of breast cancer.
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Affiliation(s)
- Shimeng Wang
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Hexing Sun
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Guanyuan Chen
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Chengyu Wu
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Bingmei Sun
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Jiajia Lin
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Danping Lin
- Department of Medical Oncology, Cancer Hospital of SUMC, Shantou 515000, China
| | - De Zeng
- Department of Medical Oncology, Cancer Hospital of SUMC, Shantou 515000, China
| | - Baohang Lin
- Department of Thyroid, Breast and Vascular Surgery, Longgang District Central Hospital of Shenzhen, Shenzhen 518116, China
| | - Guan Huang
- Department of Pathology, Longgang District Central Hospital of Shenzhen, Shenzhen 518116, China
| | - Xiaofeng Lu
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China
| | - Haoyu Lin
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China.
| | - Yuanke Liang
- Department of Thyroid and Breast Surgery, Clinical Research Center, The First Affiliated Hospital of Shantou University Medical College (SUMC), 57 Changping Road, Shantou 515041, China.
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4
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Masci D, Naro C, Puxeddu M, Urbani A, Sette C, La Regina G, Silvestri R. Recent Advances in Drug Discovery for Triple-Negative Breast Cancer Treatment. Molecules 2023; 28:7513. [PMID: 38005235 PMCID: PMC10672974 DOI: 10.3390/molecules28227513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/02/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Triple-negative breast cancer (TNBC) is one of the most heterogeneous and aggressive breast cancer subtypes with a high risk of death on recurrence. To date, TNBC is very difficult to treat due to the lack of an effective targeted therapy. However, recent advances in the molecular characterization of TNBC are encouraging the development of novel drugs and therapeutic combinations for its therapeutic management. In the present review, we will provide an overview of the currently available standard therapies and new emerging therapeutic strategies against TNBC, highlighting the promises that newly developed small molecules, repositioned drugs, and combination therapies have of improving treatment efficacy against these tumors.
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Affiliation(s)
- Domiziana Masci
- Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy; (D.M.); (A.U.)
| | - Chiara Naro
- Department of Neurosciences, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy; (C.N.); (C.S.)
- GSTeP-Organoids Research Core Facility, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy
| | - Michela Puxeddu
- Laboratory Affiliated to Istituto Pasteur Italia—Fondazione Cenci Bolognetti, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; (M.P.); (G.L.R.)
| | - Andrea Urbani
- Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy; (D.M.); (A.U.)
| | - Claudio Sette
- Department of Neurosciences, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy; (C.N.); (C.S.)
- GSTeP-Organoids Research Core Facility, Fondazione Policlinico Universitario A. Gemelli, IRCCS, 00168 Rome, Italy
| | - Giuseppe La Regina
- Laboratory Affiliated to Istituto Pasteur Italia—Fondazione Cenci Bolognetti, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; (M.P.); (G.L.R.)
| | - Romano Silvestri
- Laboratory Affiliated to Istituto Pasteur Italia—Fondazione Cenci Bolognetti, Department of Drug Chemistry and Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; (M.P.); (G.L.R.)
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5
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Chen L, Ballout F, Lu H, Hu T, Zhu S, Chen Z, Peng D. Differential Expression of NEK Kinase Family Members in Esophageal Adenocarcinoma and Barrett's Esophagus. Cancers (Basel) 2023; 15:4821. [PMID: 37835513 PMCID: PMC10571661 DOI: 10.3390/cancers15194821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/20/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023] Open
Abstract
The incidence of esophageal adenocarcinoma (EAC) has risen rapidly during the past four decades, making it the most common type of esophageal cancer in the USA and Western countries. The NEK (Never in mitosis A (NIMA) related kinase) gene family is a group of serine/threonine kinases with 11 members. Aberrant expression of NEKs has been recently found in a variety of human cancers and plays important roles in tumorigenesis, progression, and drug-resistance. However, the expression of the NEKs in EAC and its precancerous condition (Barrett's esophagus, BE) has not been investigated. In the present study, we first analyzed the TCGA and 9 GEO databases (a total of 10 databases in which 8 contain EAC and 6 contain BE) using bioinformatic approaches for NEKs expression in EAC and BE. We identified that several NEK members, such as NEK2 (7/8), NEK3 (6/8), and NEK6 (6/8), were significantly upregulated in EAC as compared to normal esophagus samples. Alternatively, NEK1 was downregulated in EAC as compared to the normal esophagus. On the contrary, genomic alterations of these NEKs are not frequent in EAC. We validated the above findings using qRT-PCR and the protein expression of NEKs in EAC cell lines using Western blotting and in primary EAC tissues using immunohistochemistry and immunofluorescence. Our data suggest that frequent upregulation of NEK2, NEK3, and NEK7 may be important in EAC.
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Affiliation(s)
- Lei Chen
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
| | - Farah Ballout
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
| | - Heng Lu
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
- Sylvester Comprehensive Cancer Center, Miami, FL 33136, USA
| | - Tianling Hu
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
| | - Shoumin Zhu
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
| | - Zheng Chen
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
- Sylvester Comprehensive Cancer Center, Miami, FL 33136, USA
| | - Dunfa Peng
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (L.C.); (F.B.); (H.L.); (T.H.); (S.Z.); (Z.C.)
- Sylvester Comprehensive Cancer Center, Miami, FL 33136, USA
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6
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Rekad Z, Ruff M, Radwanska A, Grall D, Ciais D, Van Obberghen-Schilling E. Coalescent RNA-localizing and transcriptional activities of SAM68 modulate adhesion and subendothelial basement membrane assembly. eLife 2023; 12:e85165. [PMID: 37585334 PMCID: PMC10431919 DOI: 10.7554/elife.85165] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 07/25/2023] [Indexed: 08/18/2023] Open
Abstract
Endothelial cell interactions with their extracellular matrix are essential for vascular homeostasis and expansion. Large-scale proteomic analyses aimed at identifying components of integrin adhesion complexes have revealed the presence of several RNA binding proteins (RBPs) of which the functions at these sites remain poorly understood. Here, we explored the role of the RBP SAM68 (Src associated in mitosis, of 68 kDa) in endothelial cells. We found that SAM68 is transiently localized at the edge of spreading cells where it participates in membrane protrusive activity and the conversion of nascent adhesions to mechanically loaded focal adhesions by modulation of integrin signaling and local delivery of β-actin mRNA. Furthermore, SAM68 depletion impacts cell-matrix interactions and motility through induction of key matrix genes involved in vascular matrix assembly. In a 3D environment SAM68-dependent functions in both tip and stalk cells contribute to the process of sprouting angiogenesis. Altogether, our results identify the RBP SAM68 as a novel actor in the dynamic regulation of blood vessel networks.
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Affiliation(s)
- Zeinab Rekad
- Université Côte d'Azur, CNRS, INSERM, iBVNiceFrance
| | - Michaël Ruff
- Université Côte d'Azur, CNRS, INSERM, iBVNiceFrance
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7
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Khudhair MK, Mohammed NI, Zabibah RS. Validating Sam68 expression and protein level in breast cancer. J Med Life 2023; 16:1136-1139. [PMID: 37900073 PMCID: PMC10600683 DOI: 10.25122/jml-2022-0229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 05/29/2023] [Indexed: 10/31/2023] Open
Abstract
Breast carcinoma ranks as the second most common cancer among women worldwide. Despite significant therapeutic advancements, approximately 25% of breast carcinoma cases have resistance to current treatment modalities, posing a significant challenge for patient management. This study aimed to investigate the role of Sam68 mRNA and its protein in promoting oncogenesis and breast cancer progression. Sam68 protein levels were assessed in tissue samples using an Enzyme-Linked Immunosorbent Assay kit from Sun Long Biotech. Whole RNA was isolated from malignant breast tissue samples obtained from patients. The RNA concentration was determined using an Eppendorf photometer, yielding an average concentration of 62.1±10.07 ng/µl. The purity of the isolated RNA was evaluated by measuring the A260/A280 ratio (1.9±0.07) and the A260/A230 ratio (1.7±0.3). The results indicated a significant upregulation of Sam68 mRNA expression in breast cancer tissues, supporting the findings from previous studies and indicating the correlation between altered Sam68 expression and the development of breast carcinoma, highlighting the potential significance of Sam68 in the pathogenesis of the disease. Estimating Sam68 in the blood may serve as a potential biomarker for assessing the malignant grade and metastatic spread of breast carcinoma cells.
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Affiliation(s)
- Muneer Kadhum Khudhair
- Department of Laboratory Investigation, Faculty of Science, University of Kufa, Kufa, Iraq
| | - Noaman Ibadi Mohammed
- Department of Physiology, Faculty of Veterinary Medicine, University of Kufa, Kufa, Iraq
| | - Rahman Sahib Zabibah
- Medical Laboratory Technology Department, College of Medicine, Islamic University, Najaf, Iraq
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8
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Malki I, Liepina I, Kogelnik N, Watmuff H, Robinson S, Lightfoot A, Gonchar O, Bottrill A, Fry AM, Dominguez C. Cdk1-mediated threonine phosphorylation of Sam68 modulates its RNA binding, alternative splicing activity and cellular functions. Nucleic Acids Res 2022; 50:13045-13062. [PMID: 36537190 PMCID: PMC9825155 DOI: 10.1093/nar/gkac1181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 11/17/2022] [Accepted: 11/28/2022] [Indexed: 12/24/2022] Open
Abstract
Sam68, also known as KHDRBS1, is a member of the STAR family of proteins that directly link signal transduction with post-transcriptional gene regulation. Sam68 controls the alternative splicing of many oncogenic proteins and its role is modulated by post-translational modifications, including serine/threonine phosphorylation, that differ at various stages of the cell cycle. However, the molecular basis and mechanisms of these modulations remain largely unknown. Here, we combined mass spectrometry, nuclear magnetic resonance spectroscopy and cell biology techniques to provide a comprehensive post-translational modification mapping of Sam68 at different stages of the cell cycle in HEK293 and HCT116 cells. We established that Sam68 is specifically phosphorylated at T33 and T317 by Cdk1, and demonstrated that these phosphorylation events reduce the binding of Sam68 to RNA, control its cellular localization and reduce its alternative splicing activity, leading to a reduction in the induction of apoptosis and an increase in the proliferation of HCT116 cells.
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Affiliation(s)
- Idir Malki
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Inara Liepina
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Nora Kogelnik
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Hollie Watmuff
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Sue Robinson
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Adam Lightfoot
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Oksana Gonchar
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Andrew Bottrill
- Proteomics RTP, School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Andrew M Fry
- Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Cyril Dominguez
- The Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 7RH, UK
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