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Gujrati H, Ha S, Wang BD. Deregulated microRNAs Involved in Prostate Cancer Aggressiveness and Treatment Resistance Mechanisms. Cancers (Basel) 2023; 15:3140. [PMID: 37370750 PMCID: PMC10296615 DOI: 10.3390/cancers15123140] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Prostate cancer (PCa) is the most frequently diagnosed cancer and the second leading cause of cancer deaths among American men. Complex genetic and epigenetic mechanisms are involved in the development and progression of PCa. MicroRNAs (miRNAs) are short noncoding RNAs that regulate protein expression at the post-transcriptional level by targeting mRNAs for degradation or inhibiting protein translation. In the past two decades, the field of miRNA research has rapidly expanded, and emerging evidence has revealed miRNA dysfunction to be an important epigenetic mechanism underlying a wide range of diseases, including cancers. This review article focuses on understanding the functional roles and molecular mechanisms of deregulated miRNAs in PCa aggressiveness and drug resistance based on the existing literature. Specifically, the miRNAs differentially expressed (upregulated or downregulated) in PCa vs. normal tissues, advanced vs. low-grade PCa, and treatment-responsive vs. non-responsive PCa are discussed. In particular, the oncogenic and tumor-suppressive miRNAs involved in the regulation of (1) the synthesis of the androgen receptor (AR) and its AR-V7 splice variant, (2) PTEN expression and PTEN-mediated signaling, (3) RNA splicing mechanisms, (4) chemo- and hormone-therapy resistance, and (5) racial disparities in PCa are discussed and summarized. We further provide an overview of the current advances and challenges of miRNA-based biomarkers and therapeutics in clinical practice for PCa diagnosis/prognosis and treatment.
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Affiliation(s)
- Himali Gujrati
- Department of Pharmaceutical Sciences, University of Maryland Eastern Shore School of Pharmacy, Princess Anne, MD 21853, USA
| | - Siyoung Ha
- Department of Pharmaceutical Sciences, University of Maryland Eastern Shore School of Pharmacy, Princess Anne, MD 21853, USA
| | - Bi-Dar Wang
- Department of Pharmaceutical Sciences, University of Maryland Eastern Shore School of Pharmacy, Princess Anne, MD 21853, USA
- Hormone Related Cancers Program, University of Maryland Greenebaum Comprehensive Cancer Center, Baltimore, MD 21201, USA
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2
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Nicolaides NC. The Human Glucocorticoid Receptor Beta: From Molecular Mechanisms to Clinical Implications. Endocrinology 2022; 163:6691806. [PMID: 36059139 DOI: 10.1210/endocr/bqac150] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Indexed: 11/19/2022]
Abstract
Glucocorticoids play a fundamental role in a plethora of cellular processes and physiologic functions through binding on a ubiquitously expressed receptor, the glucocorticoid receptor (GR), which functions as a ligand-activated transcription factor influencing the transcription rate of numerous genes in a positive or negative fashion. For many years, we believed that the pleiotropic actions of glucocorticoids were mediated by a single GR protein expressed by the NR3C1 gene. Nowadays, we know that the NR3C1 gene encodes 2 main receptor isoforms, the GRα and the GRβ, through alternative splicing of the last exons. Furthermore, the alternative initiation of GR mRNA translation generates 8 distinct GRα and possibly 8 different GRβ receptor isoforms. The tremendous progress of cellular, molecular, and structural biology in association with the data explosion provided by bioinformatics have enabled a deeper understanding of the role of GRβ in cellular homeostasis. In this review article, I will provide an update on the cellular properties and functions of hGRβ and summarize the current knowledge about the evolving role of the beta isoform of glucocorticoid receptor in endocrine physiology, pathophysiology, and beyond.
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Affiliation(s)
- Nicolas C Nicolaides
- Division of Endocrinology, Metabolism and Diabetes, First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, 'Aghia Sophia' Children's Hospital, Athens 11527, Greece
- Division of Endocrinology and Metabolism, Center of Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens 11527, Greece
- University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens Medical School, Athens 11527, Greece
- Department of Molecular Genetics, Function and Therapy, The Cyprus Institute of Neurology and Genetics, Nicosia 2371, Cyprus
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3
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Chen X, Zhang Q, Yang C, Liu Y, Li L. GRβ Regulates Glucocorticoid Resistance in Sudden Sensorineural Hearing Loss. Curr Pharm Biotechnol 2021; 22:1206-1215. [PMID: 33032506 DOI: 10.2174/1389201021666201008163534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/27/2020] [Accepted: 09/04/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND In recent years, the incidence of sudden deafness has gradually increased, with a very limited understanding of its etiology and pathogenesis. Glucocorticoids are the first choice of the treatment, but some hormone-resistant patients are not sensitive to glucocorticoid therapy. The pathogenesis is not yet known. In this study, we aim to construct the HEI-OC1 cell line stably overexpressing Glucocorticoid Receptor Beta (GRβ), and identify its exact role in the cases of glucocorticoidresistant sudden deafness. METHODS We used the endotoxin lipopolysaccharide-stimulated cochlear hair cells (HEI-OC1) to investigate the relationship of inflammation factor IL-2, TNF alpha, and SRp30c with the high expression GRβ. We built a stable GRβ high expression HEI-OC1 cell line and clarified its effects on the therapeutic effect of dexamethasone. MTT assay, colony formation assay, CCK-8 assay, Western blot, and RT-qPCR were utilized for characterizations. RESULTS Dexamethasone reduced the LPS-induced inflammatory response from HEI-OC1 cells (p<0.05), detected by MTT assay. Dexamethasone could protect HEI-OC1 cells, but its protective effect was weakened due to the transfection of SRp30c over-expression plasmid (p<0.05). The transfection of SRp30c over-expression plasmid in HEI-OC1 cells could elevate the expressions of GRβ (p<0.05). CONCLUSION We clarified the mechanisms of high expression of GRβ in glucocorticoid-resistant sudden sensorineural hearing loss, and proved that the inhibition of SRp30c may act as a new treatment way of glucocorticoid-resistant sudden sensorineural hearing loss.
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Affiliation(s)
- Xubo Chen
- Department of Otolaryngology, Head and Neck Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, China
| | - Qi Zhang
- College of Traditional Chinese Medicine, Jiangxi University of Traditional Chinese medicine, Nanchang, Jiangxi, 330004, China
| | - Chunping Yang
- Department of Otolaryngology, Head and Neck Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, China
| | - Yuehui Liu
- Department of Otolaryngology, Head and Neck Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, China
| | - Lihua Li
- Department of Otolaryngology, Head and Neck Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, China
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4
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Glucocorticoid Receptor β (GRβ): Beyond Its Dominant-Negative Function. Int J Mol Sci 2021; 22:ijms22073649. [PMID: 33807481 PMCID: PMC8036319 DOI: 10.3390/ijms22073649] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 12/17/2022] Open
Abstract
Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.
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Du JX, Zhu GQ, Cai JL, Wang B, Luo YH, Chen C, Cai CZ, Zhang SJ, Zhou J, Fan J, Zhu W, Dai Z. Splicing factors: Insights into their regulatory network in alternative splicing in cancer. Cancer Lett 2020; 501:83-104. [PMID: 33309781 DOI: 10.1016/j.canlet.2020.11.043] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/24/2020] [Accepted: 11/26/2020] [Indexed: 12/18/2022]
Abstract
More than 95% of all human genes are alternatively spliced after transcription, which enriches the diversity of proteins and regulates transcript and/or protein levels. The splicing isoforms produced from the same gene can manifest distinctly, even exerting opposite effects. Mounting evidence indicates that the alternative splicing (AS) mechanism is ubiquitous in various cancers and drives the generation and maintenance of various hallmarks of cancer, such as enhanced proliferation, inhibited apoptosis, invasion and metastasis, and angiogenesis. Splicing factors (SFs) play pivotal roles in the recognition of splice sites and the assembly of spliceosomes during AS. In this review, we mainly discuss the similarities and differences of SF domains, the details of SF function in AS, the effect of SF-driven pathological AS on different hallmarks of cancer, and the main drivers of SF expression level and subcellular localization. In addition, we briefly introduce the application prospects of targeted therapeutic strategies, including small-molecule inhibitors, siRNAs and splice-switching oligonucleotides (SSOs), from three perspectives (drivers, SFs and pathological AS). Finally, we share our insights into the potential direction of research on SF-centric AS-related regulatory networks.
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Affiliation(s)
- Jun-Xian Du
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Gui-Qi Zhu
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China
| | - Jia-Liang Cai
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China
| | - Biao Wang
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China
| | - Yi-Hong Luo
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Cong Chen
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Cheng-Zhe Cai
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Si-Jia Zhang
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Jian Zhou
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China
| | - Jia Fan
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China
| | - Wei Zhu
- Department of General Surgery, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China.
| | - Zhi Dai
- Liver Cancer Institute, Zhongshan Hospital, Fudan University & State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China; Key Laboratory of Carcinogenesis and Cancer Invasion, Fudan University, Ministry of Education, Shanghai, 200032, China.
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6
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Zhang Y, Wu Y, Jia Z, Cao D, Yang N, Wang Y, Cao X, Jiang J. Long non-coding RNA polymorphisms on 8q24 are associated with the prognosis of gastric cancer in a Chinese population. PeerJ 2020; 8:e8600. [PMID: 32117633 PMCID: PMC7039120 DOI: 10.7717/peerj.8600] [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] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 01/19/2020] [Indexed: 12/24/2022] Open
Abstract
Background Gastric cancer (GC) remains the third leading cause of cancer death in China. Although genome-wide association studies have identified the association between several single nucleotide polymorphisms (SNPs) on 8q24 and the risk of GC, the role of these SNPs in the prognosis of GC in Chinese populations has not yet been fully evaluated. Therefore, this study was conducted to explore the association between long non-coding RNA (lncRNA) polymorphisms on 8q24 and the prognosis of GC. Methods We genotyped 726 surgically resected GC patients to explore the association between eight SNPs in the lncRNAs CCAT1 (rs10087719, rs7816475), PCAT1 (rs1026411), PRNCR1 (rs12682421, rs13252298), and CASC8 (rs1562430, rs4871789, rs6983267) transcribed from the 8q24 locus and the prognosis of GC in a Chinese population. Results We found that the patients carrying rs12682421 AA genotypes survived for a shorter time than those with the GG/GA genotype (HR = 1.39, 95% confidence interval (CI) [1.09-1.78]). Compared with the CC/CT genotype, the TT genotype of rs1562430 was associated with an increased risk of death (HR = 1.38, 95% CI [1.06-1.80]). Furthermore, the results also identified the rs1026411 SNP as an independent prognostic factor for poor survival in GC patients. Patients carrying AA/AG variant genotypes had a 36% increased risk of death compared to those carrying the GG genotype (HR = 1.36, 95% CI [1.06-1.74]). These findings suggested that the rs12682421, rs1026411 and rs1562430 SNPs may contribute to the survival of GC and be prognostic markers for GC.
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Affiliation(s)
- Yangyu Zhang
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Yanhua Wu
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Zhifang Jia
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Donghui Cao
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Na Yang
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Yueqi Wang
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
| | - Xueyuan Cao
- Department of Gastric and Colorectal Surgery, First Hospital of Jilin University, Changchun, Jilin, China
| | - Jing Jiang
- Division of Clinical Research, First Hospital of Jilin University, Changchun, Jilin, China
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7
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Kraemer WJ, Ratamess NA, Hymer WC, Nindl BC, Fragala MS. Growth Hormone(s), Testosterone, Insulin-Like Growth Factors, and Cortisol: Roles and Integration for Cellular Development and Growth With Exercise. Front Endocrinol (Lausanne) 2020; 11:33. [PMID: 32158429 PMCID: PMC7052063 DOI: 10.3389/fendo.2020.00033] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/16/2020] [Indexed: 12/16/2022] Open
Abstract
Hormones are largely responsible for the integrated communication of several physiological systems responsible for modulating cellular growth and development. Although the specific hormonal influence must be considered within the context of the entire endocrine system and its relationship with other physiological systems, three key hormones are considered the "anabolic giants" in cellular growth and repair: testosterone, the growth hormone superfamily, and the insulin-like growth factor (IGF) superfamily. In addition to these anabolic hormones, glucocorticoids, mainly cortisol must also be considered because of their profound opposing influence on human skeletal muscle anabolism in many instances. This review presents emerging research on: (1) Testosterone signaling pathways, responses, and adaptations to resistance training; (2) Growth hormone: presents new complexity with exercise stress; (3) Current perspectives on IGF-I and physiological adaptations and complexity these hormones as related to training; and (4) Glucocorticoid roles in integrated communication for anabolic/catabolic signaling. Specifically, the review describes (1) Testosterone as the primary anabolic hormone, with an anabolic influence largely dictated primarily by genomic and possible non-genomic signaling, satellite cell activation, interaction with other anabolic signaling pathways, upregulation or downregulation of the androgen receptor, and potential roles in co-activators and transcriptional activity; (2) Differential influences of growth hormones depending on the "type" of the hormone being assayed and the magnitude of the physiological stress; (3) The exquisite regulation of IGF-1 by a family of binding proteins (IGFBPs 1-6), which can either stimulate or inhibit biological action depending on binding; and (4) Circadian patterning and newly discovered variants of glucocorticoid isoforms largely dictating glucocorticoid sensitivity and catabolic, muscle sparing, or pathological influence. The downstream integrated anabolic and catabolic mechanisms of these hormones not only affect the ability of skeletal muscle to generate force; they also have implications for pharmaceutical treatments, aging, and prevalent chronic conditions such as metabolic syndrome, insulin resistance, and hypertension. Thus, advances in our understanding of hormones that impact anabolic: catabolic processes have relevance for athletes and the general population, alike.
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Affiliation(s)
- William J. Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH, United States
- *Correspondence: William J. Kraemer
| | - Nicholas A. Ratamess
- Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ, United States
| | - Wesley C. Hymer
- Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| | - Bradley C. Nindl
- Department of Sports Medicine, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA, United States
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8
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Bjorkman KK, Buvoli M, Pugach EK, Polmear MM, Leinwand LA. miR-1/206 downregulates splicing factor Srsf9 to promote C2C12 differentiation. Skelet Muscle 2019; 9:31. [PMID: 31791406 PMCID: PMC6888935 DOI: 10.1186/s13395-019-0211-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 09/20/2019] [Indexed: 01/05/2023] Open
Abstract
Background Myogenesis is driven by specific changes in the transcriptome that occur during the different stages of muscle differentiation. In addition to controlled transcriptional transitions, several other post-transcriptional mechanisms direct muscle differentiation. Both alternative splicing and miRNA activity regulate gene expression and production of specialized protein isoforms. Importantly, disruption of either process often results in severe phenotypes as reported for several muscle diseases. Thus, broadening our understanding of the post-transcriptional pathways that operate in muscles will lay the foundation for future therapeutic interventions. Methods We employed bioinformatics analysis in concert with the well-established C2C12 cell system for predicting and validating novel miR-1 and miR-206 targets engaged in muscle differentiation. We used reporter gene assays to test direct miRNA targeting and studied C2C12 cells stably expressing one of the cDNA candidates fused to a heterologous, miRNA-resistant 3′ UTR. We monitored effects on differentiation by measuring fusion index, myotube area, and myogenic gene expression during time course differentiation experiments. Results Gene ontology analysis revealed a strongly enriched set of putative miR-1 and miR-206 targets associated with RNA metabolism. Notably, the expression levels of several candidates decreased during C2C12 differentiation. We discovered that the splicing factor Srsf9 is a direct target of both miRNAs during myogenesis. Persistent Srsf9 expression during differentiation impaired myotube formation and blunted induction of the early pro-differentiation factor myogenin as well as the late differentiation marker sarcomeric myosin, Myh8. Conclusions Our data uncover novel miR-1 and miR-206 cellular targets and establish a functional link between the splicing factor Srsf9 and myoblast differentiation. The finding that miRNA-mediated clearance of Srsf9 is a key myogenic event illustrates the coordinated and sophisticated interplay between the diverse components of the gene regulatory network.
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Affiliation(s)
- Kristen K Bjorkman
- Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA
| | - Massimo Buvoli
- Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA
| | - Emily K Pugach
- Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA
| | - Michael M Polmear
- Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA.,Department of Chemical and Biological Engineering, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA
| | - Leslie A Leinwand
- Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, University of Colorado Boulder, 3415 Colorado Ave., UCB596, Boulder, CO, 80303, USA.
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9
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Zhang Q, Lv R, Guo W, Li X. microRNA-802 inhibits cell proliferation and induces apoptosis in human cervical cancer by targeting serine/arginine-rich splicing factor 9. J Cell Biochem 2018; 120:10370-10379. [PMID: 30565744 DOI: 10.1002/jcb.28321] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 11/28/2018] [Indexed: 01/01/2023]
Abstract
microRNAs (miRNAs) play crucial roles in cancer development and progression by targeting mRNAs for degradation and/or translational repression. microRNA-802 (miR-802) has been reported as a tumor suppressor and its deregulation is observed in various human cancers. However, the prognostic value of miR-802 and its underlying mechanisms involved in human cervical cancer are poorly investigated. The purposes of this study were to explore the role of miR-802 in cervical cancer and to clarify the regulation of serine/arginine-rich splicing factor 9 (SRSF9) by miR-802. Here, we found that miR-802 was downregulated in both cervical cancer tissues and cell lines. Transfection of a miR-802 mimic into cervical cancer cells inhibited their proliferation and colony formation, and promoted cell cycle arrest at the G0/G1 phase and cell apoptosis. In addition, we found that miR-802 could directly target the 3'-untranslated region of SRSF9 and suppress SRSF9 expression. Rescue experiments revealed that overexpression of SRSF9 partially reversed the inhibition effect of miR-802 in cervical cancer cells. Overall, these findings demonstrate that miR-802 functions as a tumor suppressor in cervical cancer by targeting SRSF9, suggesting that miR-802 might serve as a potential therapeutic target in cervical cancer.
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Affiliation(s)
- Qianwen Zhang
- Gynecological Oncology Ward I, Gansu Provincial Cancer Hospital, Lanzhou City, Gansu Province, P. R. China
| | - Rui Lv
- Gynecological Oncology Ward I, Gansu Provincial Cancer Hospital, Lanzhou City, Gansu Province, P. R. China
| | - Wenjia Guo
- Department of Cancer Research Institute, Cancer Affiliated Hospital of Xinjiang Medical University, Urumqi City, Xinjiang Province, P. R. China
| | - Xiaoning Li
- Gynecological Oncology Ward I, Gansu Provincial Cancer Hospital, Lanzhou City, Gansu Province, P. R. China
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10
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Tsai CR, Lee HF, Chi CS, Yang MT, Hsu CC. Antisense oligonucleotides modulate dopa decarboxylase function in aromatic l-amino acid decarboxylase deficiency. Hum Mutat 2018; 39:2072-2082. [PMID: 30260058 DOI: 10.1002/humu.23659] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 08/22/2018] [Accepted: 09/25/2018] [Indexed: 12/24/2022]
Abstract
Aromatic l-amino acid decarboxylase deficiency (AADCD), attributed to mutations in the dopa decarboxylase (DDC) gene, is a rare neurometabolic disease resulting from a defect in the biosynthesis of dopamine and serotonin. The DDC c.714+4A>T mutation is the most prevalent mutation among patients with AADCD, and is also a founder mutation among Taiwanese patients. In this study, the molecular consequences and function of this mutation were examined in AADCD patient-derived lymphoblastoid cells. We identified novel DDC mRNA isoforms spliced with a new exon (exon 6a) in normal and c.714+4A>T lymphoblastoid cells. In addition, we identified the SR proteins (SRSF9 and SRSF6), as well as cis-elements involved in modulating the splicing of this mutated transcript. Notably, we demonstrated that antisense oligonucleotides (ASOs) were able to restore the normal mRNA splicing and increase the level of DDC protein, as well as its downstream product serotonin, in lymphoblastoid cells derived from the patient with AADCD, suggesting that these ASOs might represent a feasible alternative strategy for gene therapy of AADCD in patients with the common c.714+4A>T mutation.
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Affiliation(s)
- Chi-Ren Tsai
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan.,Department of Pediatrics, Taichung Veterans General Hospital, Taichung, 407, Taiwan
| | - Hsiu-Fen Lee
- Department of Pediatrics, Taichung Veterans General Hospital, Taichung, 407, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Ching-Shiang Chi
- School of Medicine, Chung Shan Medical University, Taichung, 402, Taiwan.,Department of Pediatrics, Tung's Taichung Metroharbor Hospital, Taichung, 435, Taiwan
| | - Ming-Te Yang
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan
| | - Chia-Chi Hsu
- Department of Pediatrics, Taichung Veterans General Hospital, Taichung, 407, Taiwan.,Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, 112, Taiwan
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11
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Transcriptional regulation of RACK1 and modulation of its expression: Role of steroid hormones and significance in health and aging. Cell Signal 2017; 35:264-271. [DOI: 10.1016/j.cellsig.2017.02.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 02/07/2017] [Accepted: 02/08/2017] [Indexed: 12/27/2022]
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12
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Buoso E, Galasso M, Ronfani M, Serafini MM, Lanni C, Corsini E, Racchi M. Role of spliceosome proteins in the regulation of glucocorticoid receptor isoforms by cortisol and dehydroepiandrosterone. Pharmacol Res 2017; 120:180-187. [PMID: 28373129 DOI: 10.1016/j.phrs.2017.03.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 03/21/2017] [Accepted: 03/21/2017] [Indexed: 10/19/2022]
Abstract
Dehydroepiandrosterone (DHEA) can counteract the activity of cortisol by modulating the glucocorticoid receptor β (GRβ) expression and antagonizing the binding of GRα to the glucocorticoid responsive element (GRE) in RACK1 (Receptor for Activated C Kinase 1) promoter. These observations are important in the context of immunosenescence and can be extended to recognize a complex hormonal balance in the control of GR isoform expression and consequently in the expression of GR responsive genes. To elucidate the mechanism of DHEA on GR alternative splicing, we investigated its possible involvement in the expression of proteins such as the Serine/arginine (SR)-Rich Splicing Factors (SRSF) regulating GR splicing, specifically SRSF9 and SRSF3 also known as SRp30c and SRp20 respectively. We demonstrated that DHEA can induce the up-regulation of GR mRNA which is preferentially directed toward the β isoform. The effect is due to an increase in expression of the splicing factor SRSF9. On the other hand cortisol up-regulated SRSF3, the splicing factor promoting GRα isoform. We demonstrated that DHEA and cortisol modulate SRSF9 and SRSF3 in a different way and our data suggest that the anti-glucocorticoid effect of DHEA, among other mechanisms, is also exerted by modulating the expression of proteins involved in the splicing of the GR pre-mRNA.
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Affiliation(s)
- Erica Buoso
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy
| | - Marilisa Galasso
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy
| | - Melania Ronfani
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy
| | - Melania Maria Serafini
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy; Scuola Universitaria Superiore IUSS Pavia, Piazza della Vittoria n.15, 27100 Pavia, Italy
| | - Cristina Lanni
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy
| | - Emanuela Corsini
- Dipartimento di Scienze Farmacologiche e Biomolecolari - Università degli Studi di Milano, Via Balzaretti 9, 20133 Milano, Italy
| | - Marco Racchi
- Dipartimento di Scienze del Farmaco - Università degli Studi di Pavia, Viale Taramelli 12/14, 27100 Pavia, Italy
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Fini ME, Schwartz SG, Gao X, Jeong S, Patel N, Itakura T, Price MO, Price FW, Varma R, Stamer WD. Steroid-induced ocular hypertension/glaucoma: Focus on pharmacogenomics and implications for precision medicine. Prog Retin Eye Res 2017; 56:58-83. [PMID: 27666015 PMCID: PMC5237612 DOI: 10.1016/j.preteyeres.2016.09.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 09/17/2016] [Accepted: 09/19/2016] [Indexed: 02/06/2023]
Abstract
Elevation of intraocular pressure (IOP) due to therapeutic use of glucocorticoids is called steroid-induced ocular hypertension (SIOH); this can lead to steroid-induced glaucoma (SIG). Glucocorticoids initiate signaling cascades ultimately affecting expression of hundreds of genes; this provides the potential for a highly personalized pharmacological response. Studies attempting to define genetic risk factors were undertaken early in the history of glucocorticoid use, however scientific tools available at that time were limited and progress stalled. In contrast, significant advances were made over the ensuing years in defining disease pathophysiology. As the genomics age emerged, it appeared the time was right to renew investigation into genetics. Pharmacogenomics is an unbiased discovery approach, not requiring an underlying hypothesis, and provides a way to pinpoint clinically significant genes and pathways that could not have been discovered any other way. Results of the first genome-wide association study to identify polymorphisms associated with SIOH, and follow-up on two novel genes linked to the disorder, GPR158 and HCG22, is discussed in the second half of the article. However, knowledge of genetic variants determining response to steroids in the eye also has value in its own right as a predictive and diagnostic tool. This article concludes with a discussion of how the Precision Medicine Initiative®, announced by U.S. President Obama in his 2015 State of the Union address, is beginning to touch the practice of ophthalmology. It is argued that SIOH/SIG may provide one of the next opportunities for effective application of precision medicine.
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Affiliation(s)
- M Elizabeth Fini
- USC Institute for Genetic Medicine and Department of Cell & Neurobiology, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA, 90089, USA.
| | - Stephen G Schwartz
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 3880 Tamiami Trail North, Naples, FL, 34103, USA.
| | - Xiaoyi Gao
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 1905 W Taylor St., Suite 235, Chicago, IL, 60612, USA.
| | - Shinwu Jeong
- USC Institute for Genetic Medicine, USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA, 90089, USA.
| | - Nitin Patel
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA, 90089, USA.
| | - Tatsuo Itakura
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA, 90089, USA.
| | - Marianne O Price
- Cornea Research Foundation of America, 9002 North Meridian Street, Indianapolis, IN, 46260, USA.
| | - Francis W Price
- Price Vision Group, 9002 North Meridian Street, Indianapolis, IN, 46260, USA.
| | - Rohit Varma
- Office of the Dean, USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, 1975 Zonal Ave., KAM 500, Los Angeles, CA, 90089, USA.
| | - W Daniel Stamer
- Department of Ophthalmology and Department of Biomedical Engineering, Duke University, AERI Room 4008, 2351 Erwin Rd, Durham, NC, 27705, USA.
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Hu J, Chen Q. The role of glucocorticoid receptor in prostate cancer progression: from bench to bedside. Int Urol Nephrol 2016; 49:369-380. [PMID: 27987128 DOI: 10.1007/s11255-016-1476-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/03/2016] [Indexed: 10/20/2022]
Abstract
Glucocorticoids are a common class of adjuvant drugs for the treatment of castration-resistant prostate cancer (CRPC) combined with antitumour or antiandrogen agents. Glucocorticoids are administered clinically because they ameliorate toxic side effects and have inhibitory effects on adrenal androgen production, acting as a pituitary suppressant. However, their effects on prostate cancer cells especially the castration resistance prostate cancer cells are poorly defined. Glucocorticoids exert effects depend to a great extent on glucocorticoid receptor. In addition to a number of glucocorticoid receptor isoforms determined, it is found that the actions of glucocorticoids through GRα are influenced by other isoforms, such as GRβ and GRγ. Recently, studies found GR confers resistance to androgen deprivation therapy, and various glucocorticoids exert distinct efficacy in CRPC. In this review, we summarized the mechanisms of glucocorticoids and its clinical appliances on the basis of present evidence.
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Affiliation(s)
- Jieping Hu
- Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China.
| | - Qingke Chen
- Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China.
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15
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Abstract
Glucocorticoids are primary stress hormones that regulate a variety of physiologic processes and are essential for life. The actions of glucocorticoids are predominantly mediated through the classic glucocorticoid receptor (GR). GRs are expressed throughout the body, but there is considerable heterogeneity in glucocorticoid sensitivity and biologic responses across tissues. The conventional belief that glucocorticoids act through a single GR protein has changed dramatically with the discovery of a diverse collection of receptor isoforms. This article provides an overview of the molecular mechanisms that regulate glucocorticoid actions, highlights the dynamic nature of hormone signaling, and discusses the molecular properties of the GR isoforms.
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16
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McBeth L, Nwaneri AC, Grabnar M, Demeter J, Nestor-Kalinoski A, Hinds TD. Glucocorticoid receptor beta increases migration of human bladder cancer cells. Oncotarget 2016; 7:27313-24. [PMID: 27036026 PMCID: PMC5053652 DOI: 10.18632/oncotarget.8430] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/14/2016] [Indexed: 12/21/2022] Open
Abstract
Bladder cancer is observed worldwide having been associated with a host of environmental and lifestyle risk factors. Recent investigations on anti-inflammatory glucocorticoid signaling point to a pathway that may impact bladder cancer. Here we show an inverse effect on the glucocorticoid receptor (GR) isoform signaling that may lead to bladder cancer. We found similar GRα expression levels in the transitional uroepithelial cancer cell lines T24 and UMUC-3. However, the T24 cells showed a significant (p < 0.05) increased expression of GRβ compared to UMUC-3, which also correlated with higher migration rates. Knockdown of GRβ in the T24 cells resulted in a decreased migration rate. Mutational analysis of the 3' untranslated region (UTR) of human GRβ revealed that miR144 might positively regulate expression. Indeed, overexpression of miR144 increased GRβ by 3.8 fold. In addition, miR144 and GRβ were upregulated during migration. We used a peptide nucleic acid conjugated to a cell penetrating-peptide (Sweet-P) to block the binding site for miR144 in the 3'UTR of GRβ. Sweet-P effectively prevented miR144 actions and decreased GRβ expression, as well as the migration of the T24 human bladder cancer cells. Therefore, GRβ may have a significant role in bladder cancer, and possibly serve as a therapeutic target for the disease.
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Affiliation(s)
- Lucien McBeth
- Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | - Assumpta C. Nwaneri
- Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | - Maria Grabnar
- Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | - Jonathan Demeter
- Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | - Andrea Nestor-Kalinoski
- Advanced Microscopy and Imaging Center, Department of Surgery, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | - Terry D. Hinds
- Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology, University of Toledo College of Medicine, Toledo, OH 43614, USA
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Radhakrishnan A, Nanjappa V, Raja R, Sathe G, Chavan S, Nirujogi RS, Patil AH, Solanki H, Renuse S, Sahasrabuddhe NA, Mathur PP, Prasad TSK, Kumar P, Califano JA, Sidransky D, Pandey A, Gowda H, Chatterjee A. Dysregulation of splicing proteins in head and neck squamous cell carcinoma. Cancer Biol Ther 2016; 17:219-29. [PMID: 26853621 DOI: 10.1080/15384047.2016.1139234] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Signaling plays an important role in regulating all cellular pathways. Altered signaling is one of the hallmarks of cancers. Phosphoproteomics enables interrogation of kinase mediated signaling pathways in biological systems. In cancers, this approach can be utilized to identify aberrantly activated pathways that potentially drive proliferation and tumorigenesis. To identify signaling alterations in head and neck squamous cell carcinoma (HNSCC), we carried out proteomic and phosphoproteomic analysis of HNSCC cell lines using a combination of tandem mass tag (TMT) labeling approach and titanium dioxide-based enrichment. We identified 4,920 phosphosites corresponding to 2,212 proteins in six HNSCC cell lines compared to a normal oral cell line. Our data indicated significant enrichment of proteins associated with splicing. We observed hyperphosphorylation of SRSF protein kinase 2 (SRPK2) and its downstream substrates in HNSCC cell lines. SRPK2 is a splicing kinase, known to phosphorylate serine/arginine (SR) rich domain proteins and regulate splicing process in eukaryotes. Although genome-wide studies have reported the contribution of alternative splicing events of several genes in the progression of cancer, the involvement of splicing kinases in HNSCC is not known. In this study, we studied the role of SRPK2 in HNSCC. Inhibition of SRPK2 resulted in significant decrease in colony forming and invasive ability in a panel of HNSCC cell lines. Our results indicate that phosphorylation of SRPK2 plays a crucial role in the regulation of splicing process in HNSCC and that splicing kinases can be developed as a new class of therapeutic target in HNSCC.
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Affiliation(s)
- Aneesha Radhakrishnan
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,b Department of Biochemistry and Molecular Biology , Pondicherry University , Puducherry , India
| | - Vishalakshi Nanjappa
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,c Amrita School of Biotechnology, Amrita University , Kollam , India
| | - Remya Raja
- a Institute of Bioinformatics, International Technology Park , Bangalore , India
| | - Gajanan Sathe
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,d Manipal University , Madhav Nagar, Manipal , India
| | - Sandip Chavan
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,d Manipal University , Madhav Nagar, Manipal , India
| | - Raja Sekhar Nirujogi
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,e Centre of Excellence in Bioinformatics, School of Life Sciences, Pondicherry University , Puducherry , India
| | - Arun H Patil
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,f School of Biotechnology, KIIT University , Bhubaneswar , India
| | - Hitendra Solanki
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,f School of Biotechnology, KIIT University , Bhubaneswar , India
| | - Santosh Renuse
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,c Amrita School of Biotechnology, Amrita University , Kollam , India
| | | | - Premendu P Mathur
- b Department of Biochemistry and Molecular Biology , Pondicherry University , Puducherry , India.,f School of Biotechnology, KIIT University , Bhubaneswar , India
| | - T S Keshava Prasad
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,c Amrita School of Biotechnology, Amrita University , Kollam , India.,e Centre of Excellence in Bioinformatics, School of Life Sciences, Pondicherry University , Puducherry , India.,g YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University , Mangalore , India
| | - Prashant Kumar
- a Institute of Bioinformatics, International Technology Park , Bangalore , India
| | - Joseph A Califano
- h Milton J Dance Head and Neck Center, Greater Baltimore Medical Center , Baltimore , MD , USA.,i Department of Otolaryngology-Head and Neck Surgery , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - David Sidransky
- i Department of Otolaryngology-Head and Neck Surgery , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Akhilesh Pandey
- j McKusick-Nathans Institute of Genetic Medicine , Baltimore , MD , USA.,k Departments of Biological Chemistry , Baltimore , MD , USA.,l Oncology and Pathology, Johns Hopkins University School of Medicine , Baltimore , MD , USA.,m Pathology, Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Harsha Gowda
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,g YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University , Mangalore , India
| | - Aditi Chatterjee
- a Institute of Bioinformatics, International Technology Park , Bangalore , India.,g YU-IOB Center for Systems Biology and Molecular Medicine, Yenepoya University , Mangalore , India
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18
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Pinto A, Malacrida B, Oieni J, Serafini MM, Davin A, Galbiati V, Corsini E, Racchi M. DHEA modulates the effect of cortisol on RACK1 expression via interference with the splicing of the glucocorticoid receptor. Br J Pharmacol 2015; 172:2918-27. [PMID: 25626076 PMCID: PMC4439885 DOI: 10.1111/bph.13097] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/21/2014] [Accepted: 01/21/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Dehydroepiandrosterone (DHEA) is thought to be an anti-glucocorticoid hormone known to be fully functional in young people but deficient in aged humans. Our previous data suggest that DHEA not only counteracts the effect of cortisol on RACK1 expression, a protein required both for the correct functioning of immune cells and for PKC-dependent pathway activation, but also modulates the inhibitory effect of cortisol on LPS-induced cytokine production. The purpose of this study was to investigate the effect of DHEA on the splicing mechanism of the human glucocorticoid receptor (GR). EXPERIMENTAL APPROACH The THP1 monocytic cell line was used as a cellular model. Cytokine production was measured by specific elisa. Western blot and real-time RT-PCR were used, where appropriate, to determine the effect of DHEA on GRs, serine/arginine-rich proteins (SRp), and RACK1 protein and mRNA. Small-interfering RNA was used to down-regulate GRβ. KEY RESULTS DHEA induced a dose-related up-regulation of GRβ and GRβ knockdown completely prevented DHEA-induced RACK1 expression and modulation of cytokine release. Moreover, we showed that DHEA influenced the expression of some components of the SRps found within the spliceosome, the main regulators of the alternative splicing of the GR gene. CONCLUSIONS AND IMPLICATIONS These data contribute to our understanding of the mechanism of action of DHEA and its effect on the immune system and as an anti-glucocorticoid agent.
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Affiliation(s)
- Antonella Pinto
- Department of Drug Sciences – Pharmacology, University of PaviaPavia, Italy
| | - Beatrice Malacrida
- Department of Drug Sciences – Pharmacology, University of PaviaPavia, Italy
| | - Jacopo Oieni
- Department of Drug Sciences – Pharmacology, University of PaviaPavia, Italy
| | | | | | - Valentina Galbiati
- Laboratory of Toxicology, DiSFeB, Università degli Studi di MilanoMilan, Italy
| | - Emanuela Corsini
- Laboratory of Toxicology, DiSFeB, Università degli Studi di MilanoMilan, Italy
| | - Marco Racchi
- Department of Drug Sciences – Pharmacology, University of PaviaPavia, Italy
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Wojtuszkiewicz A, Assaraf YG, Maas MJP, Kaspers GJL, Jansen G, Cloos J. Pre-mRNA splicing in cancer: the relevance in oncogenesis, treatment and drug resistance. Expert Opin Drug Metab Toxicol 2014; 11:673-89. [PMID: 25495223 DOI: 10.1517/17425255.2015.993316] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
INTRODUCTION Aberrant pre-mRNA splicing in cancer is emerging as an important determinant of oncogenesis, response to treatment and anticancer drug resistance. At the same time, the spliceosome has become a target for a novel class of pre-clinical chemotherapeutics with a potential future application in cancer treatment. Taken together, these findings offer novel opportunities for the enhancement of the efficacy of cancer therapy. AREAS COVERED This review presents a comprehensive overview of the molecular mechanisms involved in splicing and current developments regarding splicing aberrations in relation to several aspects of cancer formation and therapy. Identified mutations in the various components of the spliceosome and their implications for cancer prognosis are delineated. Moreover, the contribution of abnormal splicing patterns as well as deregulated splicing factors to chemoresistance is discussed, along with novel splicing-based therapeutic approaches. EXPERT OPINION Significant progress has been made in deciphering the role of splicing factors in cancer including carcinogenesis and drug resistance. Splicing-based prognostic tools as well as therapeutic options hold great potential towards improvements in cancer therapy. However, gaining more in-depth molecular insight into the consequences of mutations in various components of the splicing machinery as well as of cellular effects of spliceosome inhibition is a prerequisite to establish the role of splicing in tumor progression and treatment options, respectively.
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Affiliation(s)
- Anna Wojtuszkiewicz
- VU University Medical Center, Department of Pediatric Oncology/Hematology , Amsterdam , The Netherlands
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20
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Stechschulte LA, Wuescher L, Marino JS, Hill JW, Eng C, Hinds TD. Glucocorticoid receptor β stimulates Akt1 growth pathway by attenuation of PTEN. J Biol Chem 2014; 289:17885-94. [PMID: 24817119 DOI: 10.1074/jbc.m113.544072] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Glucocorticoids (GCs) are known inhibitors of proliferation and are commonly prescribed to cancer patients to inhibit tumor growth and induce apoptosis via the glucocorticoid receptor (GR). Because of alternative splicing, the GR exists as two isoforms, GRα and GRβ. The growth inhibitory actions of GCs are mediated via GRα, a hormone-induced transcription factor. The GRβ isoform, however, lacks helix 12 of the ligand-binding domain and cannot bind GCs. While we have previously shown that GRβ mRNA is responsive to insulin, the role of GRβ in insulin signaling and growth pathways is unknown. In the present study, we show that GRβ suppresses PTEN expression, leading to enhanced insulin-stimulated growth. These characteristics were independent of the inhibitory qualities that have been reported for GRβ on GRα. Additionally, we found that GRβ increased phosphorylation of Akt basally, which was further amplified following insulin treatment. In particular, GRβ specifically targets Akt1 in growth pathways. Our results demonstrate that the GRβ/Akt1 axis is a major player in insulin-stimulated growth.
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Affiliation(s)
- Lance A Stechschulte
- From the Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology and
| | - Leah Wuescher
- the Department of Medical Microbiology and Immunology, University of Toledo College of Medicine, Toledo, Ohio 43614
| | - Joseph S Marino
- the Department of Kinesiology, University of North Carolina at Charlotte, Charlotte, North Carolina 28223
| | - Jennifer W Hill
- From the Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology and
| | - Charis Eng
- the Genomic Medicine Institute, Lerner Research Institute and Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio 44195, and the Department of Genetics and Genome Sciences and CASE Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Terry D Hinds
- From the Center for Hypertension and Personalized Medicine, Department of Physiology and Pharmacology and
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Jain A, Wordinger RJ, Yorio T, Clark AF. Role of the alternatively spliced glucocorticoid receptor isoform GRβ in steroid responsiveness and glaucoma. J Ocul Pharmacol Ther 2014; 30:121-7. [PMID: 24506296 DOI: 10.1089/jop.2013.0239] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoid (GC)-induced ocular hypertension (OHT) is a serious side effect of GC therapy in susceptible individuals. This OHT is due to increased aqueous humor (AH) outflow resistance in the trabecular meshwork (TM) caused by GC-mediated changes in TM structure and function. GCs may also play a role in the development of primary open-angle glaucoma (POAG). Elevated cortisol levels in the AH or enhanced GC sensitivity may be one of the reasons for elevated intraocular pressure in POAG patients. The GC OHT responder population is at greater risk of developing POAG compared with non-responders. We recently have gained insight into the molecular mechanisms responsible for this differential GC responsiveness, which is attributed to differences in GC receptor isoform expression in the TM. This article summarizes current knowledge on alternative GC receptor splicing to generate GC receptor alpha (GRα) and GRβ and their roles in the regulation of GC responsiveness in normal and glaucoma TM.
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Affiliation(s)
- Ankur Jain
- 1 Department of Cell Biology and Immunology, University of North Texas Health Science Center , Fort Worth, Texas
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Zhang W, Li X, Shang X, Zhao Q, Hu Y, Xu X, He R, Duan L, Zhang F. Gene expression analysis in response to osmotic stimuli in the intervertebral disc with DNA microarray. Eur J Med Res 2013; 18:62. [PMID: 24369767 PMCID: PMC3911967 DOI: 10.1186/2047-783x-18-62] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 12/06/2013] [Indexed: 12/02/2022] Open
Abstract
Background Intervertebral disc (IVD) cells experience a broad range of physicochemical stimuli under physiologic conditions, including alterations in their osmotic environment. At present, the molecular mechanisms underlying osmotic regulation in IVD cells are poorly understood. This study aims to screen genes affected by changes in osmotic pressure in cells of subjects aged 29 to 63 years old, with top-scoring pair (TSP) method. Methods Gene expression data set GSE1648 was downloaded from Gene Expression Omnibus database, including four hyper-osmotic stimuli samples, four iso-osmotic stimuli samples, and three hypo-osmotic stimuli samples. A novel, simple method, referred to as the TSP, was used in this study. Through this method, there was no need to perform data normalization and transformation before data analysis. Results A total of five pairs of genes ((CYP2A6, FNTB), (PRPF8, TARDBP), (RPS5, OAZ1), (SLC25A3, NPM1) and (CBX3, SRSF9)) were selected based on the TSP method. We inferred that all these genes might play important roles in response to osmotic stimuli and age in IVD cells. Additionally, hyper-osmotic and iso-osmotic stimuli conditions were adverse factors for IVD cells. Conclusions We anticipate that our results will provide new thoughts and methods for the study of IVD disease.
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Affiliation(s)
| | - Xu Li
- Department of Orthopaedics, Anhui Provincial Hospital, No, 17, Road Lujiang, Hefei 230001, China.
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23
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The biology of the glucocorticoid receptor: new signaling mechanisms in health and disease. J Allergy Clin Immunol 2013; 132:1033-44. [PMID: 24084075 DOI: 10.1016/j.jaci.2013.09.007] [Citation(s) in RCA: 650] [Impact Index Per Article: 59.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 12/20/2022]
Abstract
Glucocorticoids are primary stress hormones necessary for life that regulate numerous physiologic processes in an effort to maintain homeostasis. Synthetic derivatives of these hormones have been mainstays in the clinic for treating inflammatory diseases, autoimmune disorders, and hematologic cancers. The physiologic and pharmacologic actions of glucocorticoids are mediated by the glucocorticoid receptor (GR), a member of the nuclear receptor superfamily of ligand-dependent transcription factors. Ligand-occupied GR induces or represses the transcription of thousands of genes through direct binding to DNA response elements, physically associating with other transcription factors, or both. The traditional view that glucocorticoids act through a single GR protein has changed dramatically with the discovery of a large cohort of receptor isoforms with unique expression, gene-regulatory, and functional profiles. These GR subtypes are derived from a single gene by means of alternative splicing and alternative translation initiation mechanisms. Posttranslational modification of these GR isoforms further expands the diversity of glucocorticoid responses. Here we discuss the origin and molecular properties of the GR isoforms and their contribution to the specificity and sensitivity of glucocorticoid signaling in healthy and diseased tissues.
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24
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Merkulov VM, Merkulova TI. Glucocorticoid receptor isoforms generated by alternative splicing and alternative translation initiation. ACTA ACUST UNITED AC 2012. [DOI: 10.1134/s2079059712030070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Jain A, Wordinger RJ, Yorio T, Clark AF. Spliceosome protein (SRp) regulation of glucocorticoid receptor isoforms and glucocorticoid response in human trabecular meshwork cells. Invest Ophthalmol Vis Sci 2012; 53:857-66. [PMID: 22205602 DOI: 10.1167/iovs.11-8497] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Glaucoma is a leading cause of visual impairment and blindness, with elevated intraocular pressure (IOP) as a major causative risk factor. Glucocorticoid (GC) therapy causes morphologic and biochemical changes in the trabecular meshwork (TM), an ocular tissue involved in regulating IOP, which can lead to the development of glaucoma in susceptible individuals (steroid responders). Steroid responders comprise 40% of the general population and are at higher risk of developing glaucoma. In addition, a majority of glaucoma patients are steroid responders. Differential distribution of various isoforms of GC receptor (GR) may be responsible for this heterogeneity in the steroid response. The alternatively spliced GRβ isoform acts as dominant negative regulator of classical GRα transcriptional activity. mRNA splicing is mediated by spliceosomes, which include serine-arginine rich proteins (SRps). The purpose of this study was to determine whether specific SRps regulate levels of these isoforms and thereby GC response in TM cells. METHODS Quantitative RT-PCR, Western blot analysis, and immunocytochemistry were used to determine the differential expression of different SRps (SRp20, 30c, and 40) in human normal and glaucomatous TM cell strains. Bioinformatics was used to find putative binding sites for SRp20 and SRp40 on exon 9 of the GR gene. A peptide modulator of splicing (bombesin) and SRp expression vectors were used to modulate SRp levels and determine their effects on GRα/GRβ ratios as well as dexamethasone (DEX) responsiveness via GRE- luciferase reporter activity, fibronectin, and myocilin induction in TM cells. RESULTS SRp20, SRp30c, and SRp40 regulate GR splicing and the GC response in TM cells. Modulation of SRp levels altered the GRβ/α ratio that correlated with DEX responsiveness. Bombesin decreased SRp20; increased SRp30c, SRp40 levels, and GRβ/α ratio, and suppressed DEX response in TM cells. CONCLUSIONS Relative levels of SRp20, SRp30c, and SRp40 in TM cells control differential expression of the two alternatively spliced isoforms of the GR and thereby regulate GC responsiveness. Different levels and/or activities of these SRps may account for differential GC sensitivity among the normal and glaucoma populations.
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Affiliation(s)
- Ankur Jain
- Department of Cell Biology and Anatomy, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas 76107, USA.
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26
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Yoshino H, Enokida H, Chiyomaru T, Tatarano S, Hidaka H, Yamasaki T, Gotannda T, Tachiwada T, Nohata N, Yamane T, Seki N, Nakagawa M. Tumor suppressive microRNA-1 mediated novel apoptosis pathways through direct inhibition of splicing factor serine/arginine-rich 9 (SRSF9/SRp30c) in bladder cancer. Biochem Biophys Res Commun 2011; 417:588-93. [PMID: 22178073 DOI: 10.1016/j.bbrc.2011.12.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 12/02/2011] [Indexed: 01/04/2023]
Abstract
We have previously found that restoration of tumor suppressive microRNA-1 (miR-1), induced cell apoptosis in bladder cancer (BC) cell lines. However, the apoptosis mechanism induced by miR-1 was not fully elucidated. Alternative splicing of mRNA precursors provides cancer cells with opportunities to translate many oncogenic protein variants, which promote cell proliferation and survival under unpreferable condition for cancer development. Serine/arginine-rich (SR) protein family, which involved in alternative pre-mRNA splicing, plays a critical role for regulating apoptosis by splicing apoptosis-related genes. However, transcriptional regulation of SR proteins, themselves, has not been elucidated. In this study, we focused on splicing factor serine/arginine-rich 9 (SRSF9/SRp30c) on the basis of our previous genome-wide gene expression analysis using miR-1-transfected BC cell lines because putative target sites of miR-1 are existed in 3'-untranslated region (UTR) of SRSF9 mRNA. The expression levels of mRNA of SRSF9 were extremely reduced in the miR-1 transfectants. A luciferase activity significantly decreased in the transfectants suggesting that actual binding occurred between miR-1 and 3'UTR of SRSF9 mRNA. Loss-of-function assays demonstrated that significant inhibitions of cell proliferation, migration, and invasion were observed in the si-SRSF9 transfectants. Apoptosis assays demonstrated that cell apoptosis fraction increased and that caspase-3/7 was activated in the si-SRSF9 transfectants. Our data indicated that tumor suppressive miR-1 induces apoptosis through direct inhibition of SRSF9 in BC. The identification of molecular mechanisms between miRNAs and SR proteins could provide novel apoptosis pathways and their epigenetic regulations and offer new strategies for BC treatment.
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Affiliation(s)
- Hirofumi Yoshino
- Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
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Oakley RH, Cidlowski JA. Cellular processing of the glucocorticoid receptor gene and protein: new mechanisms for generating tissue-specific actions of glucocorticoids. J Biol Chem 2011; 286:3177-84. [PMID: 21149445 PMCID: PMC3030321 DOI: 10.1074/jbc.r110.179325] [Citation(s) in RCA: 255] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Glucocorticoids regulate numerous physiological processes and are mainstays in the treatment of inflammation, autoimmune disease, and cancer. The traditional view that glucocorticoids act through a single glucocorticoid receptor (GR) protein has changed in recent years with the discovery of a large cohort of receptor subtypes arising from alternative processing of the GR gene. These isoforms differ in their expression, gene regulatory, and functional profiles. Post-translational modification of these proteins further expands GR diversity. Here, we discuss the origin and molecular properties of the GR isoforms and their contribution to the sensitivity and specificity of the glucocorticoid response.
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Affiliation(s)
- Robert H. Oakley
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Heath, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - John A. Cidlowski
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Heath, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
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Hinds TD, Ramakrishnan S, Cash HA, Stechschulte LA, Heinrich G, Najjar SM, Sanchez ER. Discovery of glucocorticoid receptor-beta in mice with a role in metabolism. Mol Endocrinol 2010; 24:1715-27. [PMID: 20660300 DOI: 10.1210/me.2009-0411] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Glucocorticoid hormones control diverse physiological processes, including metabolism and immunity, by activating the major glucocorticoid receptor (GR) isoform, GRalpha. However, humans express an alternative isoform, human (h)GRbeta, that acts as an inhibitor of hGRalpha to produce a state of glucocorticoid resistance. Indeed, evidence exists that hGRbeta contributes to many diseases and resistance to glucocorticoid hormone therapy. However, rigorous testing of the GRbeta contribution has not been possible, because rodents, especially mice, are not thought to express the beta-isoform. Here, we report expression of GRbeta mRNA and protein in the mouse. The mGRbeta isoform arises from a distinct alternative splicing mechanism utilizing intron 8, rather than exon 9 as in humans. The splicing event produces a form of beta that is similar in structure and functionality to hGRbeta. Mouse (m)GRbeta has a degenerate C-terminal region that is the same size as hGRbeta. Using a variety of newly developed tools, such as a mGRbeta-specific antibody and constructs for overexpression and short hairpin RNA knockdown, we demonstrate that mGRbeta cannot bind dexamethasone agonist, is inhibitory of mGRalpha, and is up-regulated by inflammatory signals. These properties are the same as reported for hGRbeta. Additionally, novel data is presented that mGRbeta is involved in metabolism. When murine tissue culture cells are treated with insulin, no effect on mGRalpha expression was observed, but GRbeta was elevated. In mice subjected to fasting-refeeding, a large increase of GRbeta was seen in the liver, whereas mGRalpha was unchanged. This work uncovers the much-needed rodent model of GRbeta for investigations of physiology and disease.
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Affiliation(s)
- Terry D Hinds
- Department of Physiology and Pharmacology, University of Toledo College of Medicine, 3035 Arlington Avenue, Toledo, OH 43614-5804, USA
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Alternative splicing in exon 9 of glucocorticoid receptor pre-mRNA is regulated by SRp40. Mol Biol Rep 2009; 37:1427-33. [PMID: 19343537 DOI: 10.1007/s11033-009-9529-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Accepted: 03/20/2009] [Indexed: 10/21/2022]
Abstract
Increasing evidence indicates that alternative splicing of human glucocorticoid receptor (GR) transcripts is implicated in the development of glucocorticoid resistance but the underlying mechanism was not well known. Serine/arginine-rich (SR) proteins and heterogeneous nuclear ribonucleoprotein (hnRNP) A1 play an important role in the spliceosome assembly. In this study, we analyzed the effects of different SR proteins and hnRNP A1 on the alternative splicing of GR pre-mRNA in HeLa and 293T cells using a minigene transfection assay. Our results revealed that only SRp40 could induce a GRalpha to GRbeta shift of pre-mRNA splicing in exon 9 in HeLa cells and this effect induced by SRp40 was further confirmed by small interfering RNA study. However, in 293T cells, SRp40 could not induce this shift. These results indicated that SRp40 may influence the alternative splicing of GR pre-mRNA to regulate the ratio of GRalpha to GRbeta, and this effect is cell-dependent.
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30
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Lee JG, Zheng R, McCafferty-Cepero JM, Burnstein KL, Nanus DM, Shen R. Endothelin-1 enhances the expression of the androgen receptor via activation of the c-myc pathway in prostate cancer cells. Mol Carcinog 2009; 48:141-9. [PMID: 18623111 PMCID: PMC4280021 DOI: 10.1002/mc.20462] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Increasing evidence suggests that androgen independent prostate cancer (PC) maintains a functional androgen receptor (AR) pathway despite the low levels of circulating androgen following androgen withdrawal, the molecular mechanisms of which are not well defined yet. To address this question, we investigated the effects of endothelin-1 (ET-1) on AR expression. Western analysis and RT-PCR revealed that in the presence of ET-1, levels of AR significantly increased in a time- and dose-dependent manner in LNCaP cells. Pretreatments with inhibitors of Src and phosphoinositide kinase 3 (PI-3K) suppressed ET-1-induced AR expression. As ET-1 was reported to cause a transient increase in c-myc mRNA levels, we examined the involvement of c-myc in ET-1-mediated AR expression. Transient transfection of c-myc siRNA neutralized ET-1-induced AR expression, suggesting that AR induction by ET-1 is c-myc dependent. AR can regulate the transcription of its own gene via a mechanism in which c-myc plays a crucial role. Therefore, we assessed if ET-1-induced-c-myc leads to the enhancement of AR transcription. Reporter gene assays using the previously identified AR gene enhancer containing a c-myc binding site were conducted in LNCaP cells. We found that ET-1 induced reporter gene activity from the construct containing the wild-type but not mutant c-myc binding site. Chromatin immunoprecipitation assays confirmed that ET-1 increased interaction between c-myc and c-myc binding sites in AR enhancer, suggesting that ET-1-induced AR transcription occurs via c-myc-mediated AR transcription. Together, these data support the notion that ET-1, via Src/PI-3K signaling, augments c-myc expression leading to enhanced AR expression in PC.
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Affiliation(s)
- June G Lee
- Urologic Oncology Laboratory, Department of Urology, Weill Cornell Medical College, New York, NY 10021
| | - Rong Zheng
- Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Jennifer M McCafferty-Cepero
- Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Florida 33101
| | - Kerry L Burnstein
- Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Florida 33101
| | - David M Nanus
- Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Ruoqian Shen
- Urologic Oncology Laboratory, Department of Urology, Weill Cornell Medical College, New York, NY 10021
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