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Splicing Modulation Results in Aberrant Isoforms and Protein Products of p53 Pathway Genes and the Sensitization of B Cells to Non-Genotoxic MDM2 Inhibition. Int J Mol Sci 2023; 24:ijms24032410. [PMID: 36768733 PMCID: PMC9916657 DOI: 10.3390/ijms24032410] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/18/2023] [Accepted: 01/24/2023] [Indexed: 01/27/2023] Open
Abstract
Several molecular subtypes of cancer are highly dependent on splicing for cell survival. There is a general interest in the therapeutic targeting of splicing by small molecules. E7107, a first-in-class spliceosome inhibitor, showed strong growth inhibitory activities against a large variety of human cancer xenografts. Chronic lymphocytic leukaemia (CLL) is a clinically heterogeneous hematologic malignancy, with approximately 90% of cases being TP53 wild-type at diagnosis. An increasing number of studies are evaluating alternative targeted agents in CLL, including MDM2-p53 binding antagonists. In this study, we report the effect of splicing modulation on key proteins in the p53 signalling pathway, an important cell death pathway in B cells. Splicing modulation by E7107 treatment reduced full-length MDM2 production due to exon skipping, generating a consequent reciprocal p53 increase in TP53WT cells. It was especially noteworthy that a novel p21WAF1 isoform with compromised cyclin-dependent kinase inhibitory activity was produced due to intron retention. E7107 synergized with the MDM2 inhibitor RG7388, via dual MDM2 inhibition; by E7107 at the transcript level and by RG7388 at the protein level, producing greater p53 stabilisation and apoptosis. This study provides evidence for a synergistic MDM2 and spliceosome inhibitor combination as a novel approach to treat CLL and potentially other haematological malignancies.
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2
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de la Torre C, Játiva P, Posadas I, Manzanares D, Blanco JLJ, Mellet CO, Fernández JMG, Ceña V. A β-Cyclodextrin-Based Nanoparticle with Very High Transfection Efficiency Unveils siRNA-Activated TLR3 Responses in Human Prostate Cancer Cells. Pharmaceutics 2022; 14:2424. [PMID: 36365241 PMCID: PMC9692777 DOI: 10.3390/pharmaceutics14112424] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 10/18/2023] Open
Abstract
Synthetic double-stranded small interfering RNAs (siRNAs) mimic interference RNAs (RNAi) and can bind target mRNAs with a high degree of specificity, leading to selective knockdown of the proteins they encode. However, siRNAs are very labile and must be both protected and transported by nanoparticles to be efficiently delivered into cells. In this work, we used a Janus-type polycationic amphiphilic β-cyclodextrin derivative to efficiently transfect siRNAs targeting mRNAs encoding mitogen-activated protein kinase (p42-MAPK) or Ras homolog enriched in brain (Rheb) into different cancer cell lines as well as astrocytes. We took advantage of this high transfection efficiency to simultaneously knock down p42-MAPK and Rheb to boost docetaxel (DTX)-mediated toxicity in two human prostate cancer cell lines (LNCaP and PC3). We found that double knockdown of p42-MAPK and Rheb increased DTX-toxicity in LNCaP but not in PC3 cells. However, we also observed the same effect when scramble siRNA was used, therefore pointing to an off-target effect. Indeed, we found that the siRNA we used in this work induced toll-like receptor 3 activation, leading to β-interferon production and caspase activation. We believe that this mechanism could be very useful as a general strategy to elicit an immune response against prostate cancer cells.
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Affiliation(s)
- Cristina de la Torre
- Unidad Asociada Neurodeath, Facultad de Medicina, Universidad de Castilla-La Mancha, 02006 Albacete, Spain
- Centro de Investigación Biomédica En Red (CIBER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Pablo Játiva
- Unidad Asociada Neurodeath, Facultad de Medicina, Universidad de Castilla-La Mancha, 02006 Albacete, Spain
- Centro de Investigación Biomédica En Red (CIBER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Inmaculada Posadas
- Unidad Asociada Neurodeath, Facultad de Medicina, Universidad de Castilla-La Mancha, 02006 Albacete, Spain
- Centro de Investigación Biomédica En Red (CIBER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Darío Manzanares
- Unidad Asociada Neurodeath, Facultad de Medicina, Universidad de Castilla-La Mancha, 02006 Albacete, Spain
- Centro de Investigación Biomédica En Red (CIBER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - José L. Jiménez Blanco
- Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Carmen Ortiz Mellet
- Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, 41012 Sevilla, Spain
| | | | - Valentín Ceña
- Unidad Asociada Neurodeath, Facultad de Medicina, Universidad de Castilla-La Mancha, 02006 Albacete, Spain
- Centro de Investigación Biomédica En Red (CIBER), Instituto de Salud Carlos III, 28029 Madrid, Spain
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3
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Nicholas TR, Metcalf SA, Greulich BM, Hollenhorst PC. Androgen signaling connects short isoform production to breakpoint formation at Ewing sarcoma breakpoint region 1. NAR Cancer 2021; 3:zcab033. [PMID: 34409300 PMCID: PMC8364332 DOI: 10.1093/narcan/zcab033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/26/2021] [Accepted: 07/29/2021] [Indexed: 01/23/2023] Open
Abstract
Ewing sarcoma breakpoint region 1 (EWSR1) encodes a multifunctional protein that can cooperate with the transcription factor ERG to promote prostate cancer. The EWSR1 gene is also commonly involved in oncogenic gene rearrangements in Ewing sarcoma. Despite the cancer relevance of EWSR1, its regulation is poorly understood. Here we find that in prostate cancer, androgen signaling upregulates a 5′ EWSR1 isoform by promoting usage of an intronic polyadenylation site. This isoform encodes a cytoplasmic protein that can strongly promote cell migration and clonogenic growth. Deletion of an Androgen Receptor (AR) binding site near the 5′ EWSR1 polyadenylation site abolished androgen-dependent upregulation. This polyadenylation site is also near the Ewing sarcoma breakpoint hotspot, and androgen signaling promoted R-loop and breakpoint formation. RNase H overexpression reduced breakage and 5′ EWSR1 isoform expression suggesting an R-loop dependent mechanism. These data suggest that androgen signaling can promote R-loops internal to the EWSR1 gene leading to either early transcription termination, or breakpoint formation.
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Affiliation(s)
- Taylor R Nicholas
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Stephanie A Metcalf
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
| | - Benjamin M Greulich
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
| | - Peter C Hollenhorst
- Medical Sciences, Indiana University School of Medicine, Bloomington, IN 47405, USA
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4
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Lin C, Blessing AM, Pulliam TL, Shi Y, Wilkenfeld SR, Han JJ, Murray MM, Pham AH, Duong K, Brun SN, Shaw RJ, Ittmann MM, Frigo DE. Inhibition of CAMKK2 impairs autophagy and castration-resistant prostate cancer via suppression of AMPK-ULK1 signaling. Oncogene 2021; 40:1690-1705. [PMID: 33531625 PMCID: PMC7935762 DOI: 10.1038/s41388-021-01658-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 12/18/2020] [Accepted: 01/14/2021] [Indexed: 01/30/2023]
Abstract
Previous work has suggested androgen receptor (AR) signaling mediates prostate cancer progression in part through the modulation of autophagy. However, clinical trials testing autophagy inhibition using chloroquine derivatives in men with castration-resistant prostate cancer (CRPC) have yet to yield promising results, potentially due to the side effects of this class of compounds. We hypothesized that identification of the upstream activators of autophagy in prostate cancer could highlight alternative, context-dependent targets for blocking this important cellular process during disease progression. Here, we used molecular, genetic, and pharmacological approaches to elucidate an AR-mediated autophagy cascade involving Ca2+/calmodulin-dependent protein kinase kinase 2 (CAMKK2; a kinase with a restricted expression profile), 5'-AMP-activated protein kinase (AMPK), and Unc-51 like autophagy activating kinase 1 (ULK1), but independent of canonical mechanistic target of rapamycin (mTOR) activity. Increased CAMKK2-AMPK-ULK1 signaling correlated with disease progression in genetic mouse models and patient tumor samples. Importantly, CAMKK2 disruption impaired tumor growth and prolonged survival in multiple CRPC preclinical mouse models. Similarly, an inhibitor of AMPK-ULK1 blocked autophagy, cell growth, and colony formation in prostate cancer cells. Collectively, our findings converge to demonstrate that AR can co-opt the CAMKK2-AMPK-ULK1 signaling cascade to promote prostate cancer by increasing autophagy. Thus, this pathway may represent an alternative autophagic target in CRPC.
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Affiliation(s)
- Chenchu Lin
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Alicia M Blessing
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, USA
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA
| | - Thomas L Pulliam
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, USA
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA
| | - Yan Shi
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, USA
| | - Sandi R Wilkenfeld
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Jenny J Han
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Mollianne M Murray
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Alexander H Pham
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, USA
| | - Kevin Duong
- The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Sonja N Brun
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Reuben J Shaw
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Michael M Ittmann
- Departments of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Dan L. Duncan Cancer Center, Houston, TX, USA
- Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, USA
| | - Daniel E Frigo
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Center for Nuclear Receptors and Cell Signaling, University of Houston, Houston, TX, USA.
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA.
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- The Houston Methodist Research Institute, Houston, TX, USA.
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Yuan P, Ling L, Gao X, Sun T, Miao J, Yuan X, Liu J, Wang Z, Liu B. Identification of RNA-binding protein SNRPA1 for prognosis in prostate cancer. Aging (Albany NY) 2021; 13:2895-2911. [PMID: 33460399 PMCID: PMC7880319 DOI: 10.18632/aging.202387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 10/20/2020] [Indexed: 02/06/2023]
Abstract
Prostate cancer is one of the deadliest cancers in men. RNA-binding proteins play a critical role in human cancers; however, whether they have a significant effect on the prognosis of prostate cancer has yet to be elucidated. In the present study, we performed a comprehensive analysis of RNA sequencing and clinical data from the Cancer Genome Atlas dataset and obtained differentially expressed RNA-binding proteins between prostate cancer and benign tissues. We constructed a protein-protein interaction network and Cox regression analyses were conducted to identify prognostic hub RNA-binding proteins. SNRPA1 was associated with the highest risk of poor prognosis and was therefore selected for further analysis. SNRPA1 expression was positively correlated with Gleason score and pathological TNM stage in prostate cancer patients. Furthermore, the expression profile of SNRPA1 was validated using the Oncomine, Human Protein Atlas, and Cancer Cell Line Encyclopedia databases. Meanwhile, the prognostic profile of SNRPA1 was successfully verified in GSE70769. Additionally, the results of molecular experiments revealed the proliferative role of SNRPA1 in prostate cancer cells. In summary, our findings evidenced a relationship between RNA-binding proteins and prostate cancer and indicated the prognostic significance of SNRPA1 in prostate cancer.
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Affiliation(s)
- Penghui Yuan
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Le Ling
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Xintao Gao
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Taotao Sun
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jianping Miao
- Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xianglin Yuan
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jihong Liu
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Zhihua Wang
- Department of Urology Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Bo Liu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
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Androgen receptor and its splice variant, AR-V7, differentially induce mRNA splicing in prostate cancer cells. Sci Rep 2021; 11:1393. [PMID: 33446905 PMCID: PMC7809134 DOI: 10.1038/s41598-021-81164-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 12/23/2020] [Indexed: 12/20/2022] Open
Abstract
Prostate cancer (PCa) is dependent on the androgen receptor (AR). Advanced PCa is treated with an androgen deprivation therapy-based regimen; tumors develop resistance, although they typically remain AR-dependent. Expression of constitutively active AR variants lacking the ligand-binding domain including the variant AR-V7 contributes to this resistance. AR and AR-V7, as transcription factors, regulate many of the same genes, but also have unique activities. In this study, the capacity of the two AR isoforms to regulate splicing was examined. RNA-seq data from models that endogenously express AR and express AR-V7 in response to doxycycline were used. Both AR isoforms induced multiple changes in splicing and many changes were isoform-specific. Analyses of two endogenous genes, PGAP2 and TPD52, were performed to examine differential splicing. A novel exon that appears to be a novel transcription start site was preferentially induced by AR-V7 in PGAP2 although it is induced to a lesser extent by AR. The previously described AR induced promoter 2 usage that results in a novel protein derived from TPD52 (PrLZ) was not induced by AR-V7. AR, but not AR-V7, bound to a site proximal to promoter 2, and induction was found to depend on FOXA1.
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7
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Germain L, Lafront C, Beaudette J, Karthik Poluri RT, Weidmann C, Audet-Walsh É. Alternative splicing regulation by the androgen receptor in prostate cancer cells. J Steroid Biochem Mol Biol 2020; 202:105710. [PMID: 32534106 DOI: 10.1016/j.jsbmb.2020.105710] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 03/11/2020] [Accepted: 06/02/2020] [Indexed: 11/19/2022]
Abstract
The androgen receptor (AR) is a transcription factor that drives prostate cancer (PCa) by modulating the expression of thousands of genes to promote proliferation and survival and to reprogram metabolism. However, how AR activation controls alternative splicing is mostly unknown. Our objective was to define its role in the transcriptome-wide regulation of alternative splicing. Three human PCa models-LNCaP, LAPC4, and 22Rv1 cells-were treated with and without androgens, and RNA was purified for deep-sequencing analyses (RNA-seq). Several bioinformatic tools were then used to study alternative splicing. We demonstrate that in the absence of androgens, alternative splicing complexity is similar among AR-positive PCa cells, with 48 % of all transcripts having various levels of alternative splicing. We also describe alternative splicing differences among cell lines, such as specific splicing of AR, REST, TSC2, and CTBP1. Interestingly, AR activation changed the alternative splicing of thousands of genes in all the PCa cell lines tested. Overlap between AR-sensitive alternative splicing events revealed that genes linked to cell metabolism are major targets for this specific modulation. These genes encode metabolic enzymes such as the prostate-specific membrane antigen, encoded by FOLH1, and the malate dehydrogenase 1 (MDH1). Overall, our study presents a comprehensive analysis of the PCa cell transcriptome and its modulation by AR, revealing a significant enrichment of metabolic genes in this AR-dependent regulation of alternative splicing.
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Affiliation(s)
- Lucas Germain
- Département de biochimie, microbiologie et bio-informatique, Faculté des sciences et de génie, Université Laval, Canada; Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada
| | - Camille Lafront
- Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada; Department of molecular medicine, Faculty of Medicine, Université Laval, Québec City, G1V 0A6, Canada
| | - Jolyane Beaudette
- Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada; Department of molecular medicine, Faculty of Medicine, Université Laval, Québec City, G1V 0A6, Canada
| | - Raghavendra Tejo Karthik Poluri
- Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada; Department of molecular medicine, Faculty of Medicine, Université Laval, Québec City, G1V 0A6, Canada
| | - Cindy Weidmann
- Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada
| | - Étienne Audet-Walsh
- Endocrinology - Nephrology Research Axis, Centre de recherche du CHU de Québec - Université Laval, Canada; Centre de recherche sur le cancer de l'Université Laval, Canada; Department of molecular medicine, Faculty of Medicine, Université Laval, Québec City, G1V 0A6, Canada.
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8
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Long non-coding RNA MALAT1 enhances the apoptosis of cardiomyocytes through autophagy inhibition by regulating TSC2-mTOR signaling. Biol Res 2019; 52:58. [PMID: 31783925 PMCID: PMC6883637 DOI: 10.1186/s40659-019-0265-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 11/15/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse acute myocardial infarction (AMI). This study aims to explore whether MALAT1 enhanced cardiomyocyte apoptosis via autophagy regulation and the underlying mechanisms of MALAT1 regulating autophagy. METHODS Cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The autophagy level was assessed using GFP-LC3 immunofluorescence and western blot analysis of autophagy-related proteins. RNA pull-down and RNA immunoprecipitation (RIP) was performed to analyze the binding of MALAT1 and EZH2. Chromatin immunoprecipitation (ChIP) assay was performed to analyze the binding of TSC2 promoter and EZH2. The cell apoptosis was evaluated using TUNEL staining and western blot analysis of apoptosis-related proteins. RESULTS H/R injury increased MALAT1 expression in cardiomyocytes. Furthermore, MALAT1 overexpression inhibited, whereas MALAT1 knockdown enhanced the autophagy of cardiomyocytes. Moreover, MALAT1 overexpression recruited EZH2 to TSC2 promoter regions to elevate H3K27me3 and epigenetically inhibited TSC2 transcription. Importantly, TSC2 overexpression suppressed mTOR signaling and then activated the autophagy. Further results showed that MALAT1 inhibited proliferation and enhanced apoptosis of cardiomyocytes through inhibiting TSC2 and autophagy. CONCLUSION These findings demonstrate that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis through autophagy inhibition by regulating TSC2-mTOR signaling.
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9
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Munkley J, Li L, Krishnan SRG, Hysenaj G, Scott E, Dalgliesh C, Oo HZ, Maia TM, Cheung K, Ehrmann I, Livermore KE, Zielinska H, Thompson O, Knight B, McCullagh P, McGrath J, Crundwell M, Harries LW, Daugaard M, Cockell S, Barbosa-Morais NL, Oltean S, Elliott DJ. Androgen-regulated transcription of ESRP2 drives alternative splicing patterns in prostate cancer. eLife 2019; 8:47678. [PMID: 31478829 PMCID: PMC6788855 DOI: 10.7554/elife.47678] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/02/2019] [Indexed: 12/14/2022] Open
Abstract
Prostate is the most frequent cancer in men. Prostate cancer progression is driven by androgen steroid hormones, and delayed by androgen deprivation therapy (ADT). Androgens control transcription by stimulating androgen receptor (AR) activity, yet also control pre-mRNA splicing through less clear mechanisms. Here we find androgens regulate splicing through AR-mediated transcriptional control of the epithelial-specific splicing regulator ESRP2. Both ESRP2 and its close paralog ESRP1 are highly expressed in primary prostate cancer. Androgen stimulation induces splicing switches in many endogenous ESRP2-controlled mRNA isoforms, including splicing switches correlating with disease progression. ESRP2 expression in clinical prostate cancer is repressed by ADT, which may thus inadvertently dampen epithelial splice programmes. Supporting this, treatment with the AR antagonist bicalutamide (Casodex) induced mesenchymal splicing patterns of genes including FLNB and CTNND1. Our data reveals a new mechanism of splicing control in prostate cancer with important implications for disease progression.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Ling Li
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and HealthUniversity of ExeterExeterUnited Kingdom
| | - S R Gokul Krishnan
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Gerald Hysenaj
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Emma Scott
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Caroline Dalgliesh
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Htoo Zarni Oo
- Department of Urologic SciencesUniversity of British ColumbiaVancouverCanada,Vancouver Prostate CentreVancouverCanada
| | - Teresa Mendes Maia
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de MedicinaUniversidade de LisboaLisboaPortugal,VIB Center for Medical BiotechnologyVIBGhentBelgium,VIB Proteomics CoreVIBGhentBelgium,Department for Biomolecular MedicineGhent UniversityGhentBelgium
| | - Kathleen Cheung
- Bioinformatics Support Unit, Faculty of Medical SciencesNewcastle UniversityNewcastleUnited Kingdom
| | - Ingrid Ehrmann
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Karen E Livermore
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
| | - Hanna Zielinska
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and HealthUniversity of ExeterExeterUnited Kingdom
| | - Oliver Thompson
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and HealthUniversity of ExeterExeterUnited Kingdom
| | - Bridget Knight
- NIHR Exeter Clinical Research FacilityRoyal Devon and Exeter NHS Foundation TrustExeterUnited Kingdom
| | - Paul McCullagh
- Department of PathologyRoyal Devon and Exeter NHS Foundation TrustExeterUnited Kingdom
| | - John McGrath
- Exeter Surgical Health Services Research UnitRoyal Devon and Exeter NHS Foundation TrustExeterUnited Kingdom
| | - Malcolm Crundwell
- Department of UrologyRoyal Devon and Exeter NHS Foundation TrustExeterUnited Kingdom
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and HealthUniversity of ExeterExeterUnited Kingdom
| | - Mads Daugaard
- Department of Urologic SciencesUniversity of British ColumbiaVancouverCanada,Vancouver Prostate CentreVancouverCanada
| | - Simon Cockell
- Bioinformatics Support Unit, Faculty of Medical SciencesNewcastle UniversityNewcastleUnited Kingdom
| | - Nuno L Barbosa-Morais
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de MedicinaUniversidade de LisboaLisboaPortugal
| | - Sebastian Oltean
- Institute of Biomedical and Clinical Sciences, Medical School, College of Medicine and HealthUniversity of ExeterExeterUnited Kingdom
| | - David J Elliott
- Institute of Genetic MedicineUniversity of NewcastleNewcastleUnited Kingdom
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10
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Munkley J, Maia TM, Ibarluzea N, Livermore KE, Vodak D, Ehrmann I, James K, Rajan P, Barbosa-Morais NL, Elliott DJ. Androgen-dependent alternative mRNA isoform expression in prostate cancer cells. F1000Res 2018; 7:1189. [PMID: 30271587 PMCID: PMC6143958 DOI: 10.12688/f1000research.15604.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/30/2018] [Indexed: 12/18/2022] Open
Abstract
Background: Androgen steroid hormones are key drivers of prostate cancer. Previous work has shown that androgens can drive the expression of alternative mRNA isoforms as well as transcriptional changes in prostate cancer cells. Yet to what extent androgens control alternative mRNA isoforms and how these are expressed and differentially regulated in prostate tumours is unknown. Methods: Here we have used RNA-Seq data to globally identify alternative mRNA isoform expression under androgen control in prostate cancer cells, and profiled the expression of these mRNA isoforms in clinical tissue. Results: Our data indicate androgens primarily switch mRNA isoforms through alternative promoter selection. We detected 73 androgen regulated alternative transcription events, including utilisation of 56 androgen-dependent alternative promoters, 13 androgen-regulated alternative splicing events, and selection of 4 androgen-regulated alternative 3' mRNA ends. 64 of these events are novel to this study, and 26 involve previously unannotated isoforms. We validated androgen dependent regulation of 17 alternative isoforms by quantitative PCR in an independent sample set. Some of the identified mRNA isoforms are in genes already implicated in prostate cancer (including LIG4, FDFT1 and RELAXIN), or in genes important in other cancers (e.g. NUP93 and MAT2A). Importantly, analysis of transcriptome data from 497 tumour samples in the TGCA prostate adenocarcinoma (PRAD) cohort identified 13 mRNA isoforms (including TPD52, TACC2 and NDUFV3) that are differentially regulated in localised prostate cancer relative to normal tissue, and 3 ( OSBPL1A, CLK3 and TSC22D3) which change significantly with Gleason grade and tumour stage. Conclusions: Our findings dramatically increase the number of known androgen regulated isoforms in prostate cancer, and indicate a highly complex response to androgens in prostate cancer cells that could be clinically important.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, Newcastle, NE1 3BZ, UK
| | - Teresa M. Maia
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, 1649-028, Portugal
- VIB Proteomics Core, Albert Baertsoenkaai 3, Ghent, 9000, Belgium
| | - Nekane Ibarluzea
- Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, Newcastle, NE1 3BZ, UK
- Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Barakaldo, 48903, Spain
- Centre for Biomedical Research on Rare Diseases (CIBERER), ISCIII, Valencia, 46010, Spain
| | - Karen E. Livermore
- Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, Newcastle, NE1 3BZ, UK
| | - Daniel Vodak
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Ingrid Ehrmann
- Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, Newcastle, NE1 3BZ, UK
| | - Katherine James
- Interdisciplinary Computing and Complex BioSystems Research Group, Newcastle University, Newcastle upon Tyne, NE4 5TG, UK
- Life and Earth Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
| | - Prabhakar Rajan
- Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, EC1M 6BQ, UK
| | - Nuno L. Barbosa-Morais
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, 1649-028, Portugal
| | - David J. Elliott
- Institute of Genetic Medicine, University of Newcastle, Newcastle upon Tyne, Newcastle, NE1 3BZ, UK
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11
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Munkley J, Livermore K, Rajan P, Elliott DJ. RNA splicing and splicing regulator changes in prostate cancer pathology. Hum Genet 2017; 136:1143-1154. [PMID: 28382513 PMCID: PMC5602090 DOI: 10.1007/s00439-017-1792-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 03/29/2017] [Indexed: 11/26/2022]
Abstract
Changes in mRNA splice patterns have been associated with key pathological mechanisms in prostate cancer progression. The androgen receptor (abbreviated AR) transcription factor is a major driver of prostate cancer pathology and activated by androgen steroid hormones. Selection of alternative promoters by the activated AR can critically alter gene function by switching mRNA isoform production, including creating a pro-oncogenic isoform of the normally tumour suppressor gene TSC2. A number of androgen-regulated genes generate alternatively spliced mRNA isoforms, including a prostate-specific splice isoform of ST6GALNAC1 mRNA. ST6GALNAC1 encodes a sialyltransferase that catalyses the synthesis of the cancer-associated sTn antigen important for cell mobility. Genetic rearrangements occurring early in prostate cancer development place ERG oncogene expression under the control of the androgen-regulated TMPRSS2 promoter to hijack cell behaviour. This TMPRSS2-ERG fusion gene shows different patterns of alternative splicing in invasive versus localised prostate cancer. Alternative AR mRNA isoforms play a key role in the generation of prostate cancer drug resistance, by providing a mechanism through which prostate cancer cells can grow in limited serum androgen concentrations. A number of splicing regulator proteins change expression patterns in prostate cancer and may help drive key stages of disease progression. Up-regulation of SRRM4 establishes neuronal splicing patterns in neuroendocrine prostate cancer. The splicing regulators Sam68 and Tra2β increase expression in prostate cancer. The SR protein kinase SRPK1 that modulates the activity of SR proteins is up-regulated in prostate cancer and has already given encouraging results as a potential therapeutic target in mouse models.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle, NE1 3BZ, England, UK
| | - Karen Livermore
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle, NE1 3BZ, England, UK
| | - Prabhakar Rajan
- Barts Cancer Institute, John Vane Science Centre, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - David J Elliott
- Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle, NE1 3BZ, England, UK.
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12
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Munkley J, McClurg UL, Livermore KE, Ehrmann I, Knight B, Mccullagh P, Mcgrath J, Crundwell M, Harries LW, Leung HY, Mills IG, Robson CN, Rajan P, Elliott DJ. The cancer-associated cell migration protein TSPAN1 is under control of androgens and its upregulation increases prostate cancer cell migration. Sci Rep 2017; 7:5249. [PMID: 28701765 PMCID: PMC5507901 DOI: 10.1038/s41598-017-05489-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/30/2017] [Indexed: 02/06/2023] Open
Abstract
Cell migration drives cell invasion and metastatic progression in prostate cancer and is a major cause of mortality and morbidity. However the mechanisms driving cell migration in prostate cancer patients are not fully understood. We previously identified the cancer-associated cell migration protein Tetraspanin 1 (TSPAN1) as a clinically relevant androgen regulated target in prostate cancer. Here we find that TSPAN1 is acutely induced by androgens, and is significantly upregulated in prostate cancer relative to both normal prostate tissue and benign prostate hyperplasia (BPH). We also show for the first time, that TSPAN1 expression in prostate cancer cells controls the expression of key proteins involved in cell migration. Stable upregulation of TSPAN1 in both DU145 and PC3 cells significantly increased cell migration and induced the expression of the mesenchymal markers SLUG and ARF6. Our data suggest TSPAN1 is an androgen-driven contributor to cell survival and motility in prostate cancer.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK.
| | - Urszula L McClurg
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - Karen E Livermore
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Ingrid Ehrmann
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Bridget Knight
- NIHR Exeter Clinical Research Facility, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Paul Mccullagh
- Department of Pathology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - John Mcgrath
- Exeter Surgical Health Services Research Unit, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Malcolm Crundwell
- Department of Urology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter, Devon, UK
| | - Hing Y Leung
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Ian G Mills
- Prostate Cancer Research Group, Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo and Oslo University Hospitals, Forskningsparken, Gaustadalléen 21, N-0349, Oslo, Norway
- Department of Molecular Oncology, Institute for Cancer Research, Oslo University Hospital HE - Norwegian Radium Hospital, Montebello, Ian G. Mills, NO-0424, Oslo, Norway
- Movember/Prostate Cancer UK Centre of Excellence for Prostate Cancer Research, Centre for Cancer Research and Cell Biology (CCRCB), Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7AE, UK
| | - Craig N Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - Prabhakar Rajan
- Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London, EC1M 6BQ, UK
| | - David J Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
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13
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Munkley J. Glycosylation is a global target for androgen control in prostate cancer cells. Endocr Relat Cancer 2017; 24:R49-R64. [PMID: 28159857 DOI: 10.1530/erc-16-0569] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 02/03/2017] [Indexed: 12/17/2022]
Abstract
Changes in glycan composition are common in cancer and can play important roles in all of the recognised hallmarks of cancer. We recently identified glycosylation as a global target for androgen control in prostate cancer cells and further defined a set of 8 glycosylation enzymes (GALNT7, ST6GalNAc1, GCNT1, UAP1, PGM3, CSGALNACT1, ST6GAL1 and EDEM3), which are also significantly upregulated in prostate cancer tissue. These 8 enzymes are under direct control of the androgen receptor (AR) and are linked to the synthesis of important cancer-associated glycans such as sialyl-Tn (sTn), sialyl LewisX (SLeX), O-GlcNAc and chondroitin sulfate. Glycosylation has a key role in many important biological processes in cancer including cell adhesion, migration, interactions with the cell matrix, immune surveillance, cell signalling and cellular metabolism. Our results suggest that alterations in patterns of glycosylation via androgen control might modify some or all of these processes in prostate cancer. The prostate is an abundant secretor of glycoproteins of all types, and alterations in glycans are, therefore, attractive as potential biomarkers and therapeutic targets. Emerging data on these often overlooked glycan modifications have the potential to improve risk stratification and therapeutic strategies in patients with prostate cancer.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic MedicineNewcastle University, Newcastle-upon-Tyne, UK
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14
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Khan AS, Frigo DE. A spatiotemporal hypothesis for the regulation, role, and targeting of AMPK in prostate cancer. Nat Rev Urol 2017; 14:164-180. [PMID: 28169991 PMCID: PMC5672799 DOI: 10.1038/nrurol.2016.272] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The 5'-AMP-activated protein kinase (AMPK) is a master regulator of cellular homeostasis. Despite AMPK's known function in physiology, its role in pathological processes such as prostate cancer is enigmatic. However, emerging evidence is now beginning to decode the paradoxical role of AMPK in cancer and, therefore, inform clinicians if - and how - AMPK could be therapeutically targeted. Spatiotemporal regulation of AMPK complexes could be one of the mechanisms that governs this kinase's role in cancer. We hypothesize that different upstream stimuli will activate select subcellular AMPK complexes. This hypothesis is supported by the distinct subcellular locations of the various AMPK subunits. Each of these unique AMPK complexes regulates discrete downstream processes that can be tumour suppressive or oncogenic. AMPK's final biological output is then determined by the weighted net function of these downstream signalling events, influenced by additional prostate-specific signalling.
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Affiliation(s)
- Ayesha S. Khan
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX USA
| | - Daniel E. Frigo
- Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX USA
- Genomic Medicine Program, The Houston Methodist Research Institute, Houston, TX USA
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15
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Munkley J, Vodak D, Livermore KE, James K, Wilson BT, Knight B, Mccullagh P, Mcgrath J, Crundwell M, Harries LW, Leung HY, Robson CN, Mills IG, Rajan P, Elliott DJ. Glycosylation is an Androgen-Regulated Process Essential for Prostate Cancer Cell Viability. EBioMedicine 2016; 8:103-116. [PMID: 27428423 PMCID: PMC4919605 DOI: 10.1016/j.ebiom.2016.04.018] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/04/2016] [Accepted: 04/15/2016] [Indexed: 12/20/2022] Open
Abstract
Steroid androgen hormones play a key role in the progression and treatment of prostate cancer, with androgen deprivation therapy being the first-line treatment used to control cancer growth. Here we apply a novel search strategy to identify androgen-regulated cellular pathways that may be clinically important in prostate cancer. Using RNASeq data, we searched for genes that showed reciprocal changes in expression in response to acute androgen stimulation in culture, and androgen deprivation in patients with prostate cancer. Amongst 700 genes displaying reciprocal expression patterns we observed a significant enrichment in the cellular process glycosylation. Of 31 reciprocally-regulated glycosylation enzymes, a set of 8 (GALNT7, ST6GalNAc1, GCNT1, UAP1, PGM3, CSGALNACT1, ST6GAL1 and EDEM3) were significantly up-regulated in clinical prostate carcinoma. Androgen exposure stimulated synthesis of glycan structures downstream of this core set of regulated enzymes including sialyl-Tn (sTn), sialyl Lewis(X) (SLe(X)), O-GlcNAc and chondroitin sulphate, suggesting androgen regulation of the core set of enzymes controls key steps in glycan synthesis. Expression of each of these enzymes also contributed to prostate cancer cell viability. This study identifies glycosylation as a global target for androgen control, and suggests loss of specific glycosylation enzymes might contribute to tumour regression following androgen depletion therapy.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK.
| | - Daniel Vodak
- Bioinformatics Core Facility, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Karen E Livermore
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Katherine James
- Interdisciplinary Computing and Complex BioSystems Research Group, Newcastle University, Newcastle upon Tyne, UK
| | - Brian T Wilson
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK; Northern Genetics Service, Newcastle Upon Tyne NHS Foundation Trust, International Centre for Life, Newcastle upon Tyne, UK
| | - Bridget Knight
- NIHR Exeter Clinical Research Facility, RD&E NHS Foundation Trust, UK
| | | | - John Mcgrath
- Exeter Surgical Health Services Research Unit, RD&E NHS Foundation Trust, UK
| | - Malcolm Crundwell
- Department of Urology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter, Devon EX1 2LU, UK
| | - Hing Y Leung
- Cancer Research UK Beatson Institute, Glasgow G61 1BD, UK; Institute of Cancer Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Craig N Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Ian G Mills
- Prostate Cancer Research Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo and Oslo University Hospitals, Oslo, Norway; Departments of Molecular Oncology, Institute of Cancer Research and Radium Hospital, Oslo, Norway; PCUK/Movember Centre of Excellence for Prostate Cancer Research, Centre for Cancer Research and Cell Biology (CCRCB), Queen's University, Belfast, UK
| | - Prabhakar Rajan
- Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ, UK
| | - David J Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
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16
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Kato M, Banuelos CA, Imamura Y, Leung JK, Caley DP, Wang J, Mawji NR, Sadar MD. Cotargeting Androgen Receptor Splice Variants and mTOR Signaling Pathway for the Treatment of Castration-Resistant Prostate Cancer. Clin Cancer Res 2015; 22:2744-54. [PMID: 26712685 DOI: 10.1158/1078-0432.ccr-15-2119] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 12/13/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE The PI3K/Akt/mTOR pathway is activated in most castration-resistant prostate cancers (CRPC). Transcriptionally active androgen receptor (AR) plays a role in the majority of CRPCs. Therefore, cotargeting full-length (FL) AR and PI3K/Akt/mTOR signaling has been proposed as a possible, more effective therapeutic approach for CRPC. However, truncated AR-splice variants (AR-V) that are constitutively active and dominant over FL-AR are associated with tumor progression and resistance mechanisms in CRPC. It is currently unknown how blocking the PI3K/Akt/mTOR pathway impacts prostate cancer driven by AR-Vs. Here, we evaluated the efficacy and mechanism of combination therapy to block mTOR activity together with EPI-002, an AR N-terminal domain (NTD) antagonist that blocks the transcriptional activities of FL-AR and AR-Vs in models of CRPC. EXPERIMENTAL DESIGN To determine the functional roles of FL-AR, AR-Vs, and PI3K/Akt/mTOR pathways, we employed EPI-002 or enzalutamide and BEZ235 (low dose) or everolimus in human prostate cancer cells that express FL-AR or FL-AR and AR-Vs (LNCaP95). Gene expression and efficacy were examined in vitro and in vivo RESULTS EPI-002 had antitumor activity in enzalutamide-resistant LNCaP95 cells that was associated with decreased expression of AR-V target genes (e.g., UBE2C). Inhibition of mTOR provided additional blockade of UBE2C expression. A combination of EPI-002 and BEZ235 decreased the growth of LNCaP95 cells in vitro and in vivo CONCLUSIONS Cotargeting mTOR and AR-NTD to block transcriptional activities of FL-AR and AR-Vs provided maximum antitumor efficacy in PTEN-null, enzalutamide-resistant CRPC. Clin Cancer Res; 22(11); 2744-54. ©2015 AACR.
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Affiliation(s)
- Minoru Kato
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Carmen A Banuelos
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Yusuke Imamura
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Jacky K Leung
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Daniel P Caley
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Jun Wang
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Nasrin R Mawji
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Marianne D Sadar
- Department of Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada.
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17
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Dasgupta B, Chhipa RR. Evolving Lessons on the Complex Role of AMPK in Normal Physiology and Cancer. Trends Pharmacol Sci 2015; 37:192-206. [PMID: 26711141 DOI: 10.1016/j.tips.2015.11.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 02/08/2023]
Abstract
AMP kinase (AMPK) is an evolutionarily conserved enzyme required for adaptive responses to various physiological and pathological conditions. AMPK executes numerous cellular functions, some of which are often perceived at odds with each other. While AMPK is essential for embryonic growth and development, its full impact in adult tissues is revealed under stressful situations that organisms face in the real world. Conflicting reports about its cellular functions, particularly in cancer, are intriguing and a growing number of AMPK activators are being developed to treat human diseases such as cancer and diabetes. Whether these drugs will have only context-specific benefits or detrimental effects in the treatment of human cancer will be a subject of intense research. Here we review the current state of AMPK research with an emphasis on cancer and discuss the yet unresolved context-dependent functions of AMPK in human cancer.
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Affiliation(s)
- Biplab Dasgupta
- Division of Oncology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
| | - Rishi Raj Chhipa
- Division of Oncology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
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18
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Munkley J, Oltean S, Vodák D, Wilson BT, Livermore KE, Zhou Y, Star E, Floros VI, Johannessen B, Knight B, McCullagh P, McGrath J, Crundwell M, Skotheim RI, Robson CN, Leung HY, Harries LW, Rajan P, Mills IG, Elliott DJ. The androgen receptor controls expression of the cancer-associated sTn antigen and cell adhesion through induction of ST6GalNAc1 in prostate cancer. Oncotarget 2015; 6:34358-74. [PMID: 26452038 PMCID: PMC4741458 DOI: 10.18632/oncotarget.6024] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 09/09/2015] [Indexed: 01/17/2023] Open
Abstract
Patterns of glycosylation are important in cancer, but the molecular mechanisms that drive changes are often poorly understood. The androgen receptor drives prostate cancer (PCa) development and progression to lethal metastatic castration-resistant disease. Here we used RNA-Seq coupled with bioinformatic analyses of androgen-receptor (AR) binding sites and clinical PCa expression array data to identify ST6GalNAc1 as a direct and rapidly activated target gene of the AR in PCa cells. ST6GalNAc1 encodes a sialytransferase that catalyses formation of the cancer-associated sialyl-Tn antigen (sTn), which we find is also induced by androgen exposure. Androgens induce expression of a novel splice variant of the ST6GalNAc1 protein in PCa cells. This splice variant encodes a shorter protein isoform that is still fully functional as a sialyltransferase and able to induce expression of the sTn-antigen. Surprisingly, given its high expression in tumours, stable expression of ST6GalNAc1 in PCa cells reduced formation of stable tumours in mice, reduced cell adhesion and induced a switch towards a more mesenchymal-like cell phenotype in vitro. ST6GalNAc1 has a dynamic expression pattern in clinical datasets, beingsignificantly up-regulated in primary prostate carcinoma but relatively down-regulated in established metastatic tissue. ST6GalNAc1 is frequently upregulated concurrently with another important glycosylation enzyme GCNT1 previously associated with prostate cancer progression and implicated in Sialyl Lewis X antigen synthesis. Together our data establishes an androgen-dependent mechanism for sTn antigen expression in PCa, and are consistent with a general role for the androgen receptor in driving important coordinate changes to the glycoproteome during PCa progression.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Sebastian Oltean
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - Daniel Vodák
- Bioinformatics Core Facility, Institute for Cancer Genetics and Informatics, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Brian T. Wilson
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Karen E. Livermore
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Yan Zhou
- Beatson Institute for Cancer Research, Glasgow, UK
| | - Eleanor Star
- Microvascular Research Laboratories, School of Physiology and Pharmacology, University of Bristol, Bristol, UK
| | - Vasileios I. Floros
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Bjarne Johannessen
- Department of Molecular Oncology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Bridget Knight
- NIHR Exeter Clinical Research Facility, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Paul McCullagh
- Department of Pathology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - John McGrath
- Exeter Surgical Health Services Research Unit, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Malcolm Crundwell
- Department of Urology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Rolf I. Skotheim
- Department of Molecular Oncology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Craig N. Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - Hing Y. Leung
- Beatson Institute for Cancer Research, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Lorna W. Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter, Devon, UK
| | - Prabhakar Rajan
- Beatson Institute for Cancer Research, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Ian G. Mills
- Prostate Cancer Research Group, Centre for Molecular Medicine Norway (NCMM), University of Oslo and Oslo University Hospitals, Oslo, Norway
- Departments of Molecular Oncology, Institute of Cancer Research and Radium Hospital, Oslo, Norway
- PCUK/Movember Centre of Excellence for Prostate Cancer Research, Centre for Cancer Research and Cell Biology (CCRCB), Queen's University, Belfast, UK
| | - David J. Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
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19
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Chappell WH, Abrams SL, Lertpiriyapong K, Fitzgerald TL, Martelli AM, Cocco L, Rakus D, Gizak A, Terrian D, Steelman LS, McCubrey JA. Novel roles of androgen receptor, epidermal growth factor receptor, TP53, regulatory RNAs, NF-kappa-B, chromosomal translocations, neutrophil associated gelatinase, and matrix metalloproteinase-9 in prostate cancer and prostate cancer stem cells. Adv Biol Regul 2015; 60:64-87. [PMID: 26525204 DOI: 10.1016/j.jbior.2015.10.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 10/02/2015] [Indexed: 12/19/2022]
Abstract
Approximately one in six men will be diagnosed with some form of prostate cancer in their lifetime. Over 250,000 men worldwide die annually due to complications from prostate cancer. While advancements in prostate cancer screening and therapies have helped in lowering this statistic, better tests and more effective therapies are still needed. This review will summarize the novel roles of the androgen receptor (AR), epidermal growth factor receptor (EGFR), the EGFRvIII variant, TP53, long-non-coding RNAs (lncRNAs), microRNAs (miRs), NF-kappa-B, chromosomal translocations, neutrophil associated gelatinase, (NGAL), matrix metalloproteinase-9 (MMP-9), the tumor microenvironment and cancer stem cells (CSC) have on the diagnosis, development and treatment of prostate cancer.
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Affiliation(s)
- William H Chappell
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Stephen L Abrams
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Kvin Lertpiriyapong
- Department of Comparative Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Timothy L Fitzgerald
- Department of Surgery, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Alberto M Martelli
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Lucio Cocco
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, Bologna, Italy
| | - Dariusz Rakus
- Department of Animal Molecular Physiology, Institute of Experimental Biology, Wroclaw University, Wroclaw, Poland
| | - Agnieszka Gizak
- Department of Animal Molecular Physiology, Institute of Experimental Biology, Wroclaw University, Wroclaw, Poland
| | - David Terrian
- Department of Anatomy and Cell Biology, Brody School of Medicine at East Carolina University, Greenville, NC, USA
| | - Linda S Steelman
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - James A McCubrey
- Department of Microbiology & Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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20
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Munkley J, Livermore KE, McClurg UL, Kalna G, Knight B, McCullagh P, McGrath J, Crundwell M, Leung HY, Robson CN, Harries LW, Rajan P, Elliott DJ. The PI3K regulatory subunit gene PIK3R1 is under direct control of androgens and repressed in prostate cancer cells. Oncoscience 2015; 2:755-64. [PMID: 26501081 PMCID: PMC4606009 DOI: 10.18632/oncoscience.243] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 09/12/2015] [Indexed: 12/21/2022] Open
Abstract
Androgen receptor (AR) signalling and the PI3K pathway mediate survival signals in prostate cancer, and have been shown to regulate each other by reciprocal negative feedback, such that inhibition of one activates the other. Understanding the reciprocal regulation of these pathways is important for disease management as tumour cells can adapt and survive when either single pathway is inhibited pharmacologically. We recently carried out genome-wide exon-specific profiling of prostate cancer cells to identify novel androgen-regulated transcriptional events. Here we interrogated this dataset for novel androgen-regulated genes associated with the PI3K pathway. We find that the PI3K regulatory subunits PIK3R1 (p85α) and PIK3R3 (p55γ) are direct targets of the AR which are rapidly repressed by androgens in LNCaP cells. Further characterisation revealed that the PIK3CA p110α catalytic subunit is also indirectly regulated by androgens at the protein level. We show that PIK3R1 mRNA is significantly under-expressed in prostate cancer (PCa) tissue, and provide data to suggest a context-dependent regulatory mechanism whereby repression of the p85α protein by the AR results in destabilisation of the PI3K p110α catalytic subunit and downstream PI3K pathway inhibition that functionally affects the properties of prostate cancer cells.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Karen E. Livermore
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Urszula L. McClurg
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - Gabriela Kalna
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Bridget Knight
- NIHR Exeter Clinical Research Facility, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Paul McCullagh
- Department of Pathology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - John McGrath
- Exeter Surgical Health Services Research Unit, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Malcolm Crundwell
- Department of Urology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Hing Y. Leung
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Craig N. Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - Lorna W. Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter, Devon, UK
| | - Prabhakar Rajan
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - David J. Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
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21
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Chan SC, Selth LA, Li Y, Nyquist MD, Miao L, Bradner JE, Raj GV, Tilley WD, Dehm SM. Targeting chromatin binding regulation of constitutively active AR variants to overcome prostate cancer resistance to endocrine-based therapies. Nucleic Acids Res 2015; 43:5880-97. [PMID: 25908785 PMCID: PMC4499120 DOI: 10.1093/nar/gkv262] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/16/2015] [Indexed: 11/29/2022] Open
Abstract
Androgen receptor (AR) variants (AR-Vs) expressed in prostate cancer (PCa) lack the AR ligand binding domain (LBD) and function as constitutively active transcription factors. AR-V expression in patient tissues or circulating tumor cells is associated with resistance to AR-targeting endocrine therapies and poor outcomes. Here, we investigated the mechanisms governing chromatin binding of AR-Vs with the goal of identifying therapeutic vulnerabilities. By chromatin immunoprecipitation and sequencing (ChIP-seq) and complementary biochemical experiments, we show that AR-Vs display a binding preference for the same canonical high-affinity androgen response elements (AREs) that are preferentially engaged by AR, albeit with lower affinity. Dimerization was an absolute requirement for constitutive AR-V DNA binding and transcriptional activation. Treatment with the bromodomain and extraterminal (BET) inhibitor JQ1 resulted in inhibition of AR-V chromatin binding and impaired AR-V driven PCa cell growth in vitro and in vivo. Importantly, this was associated with a novel JQ1 action of down-regulating AR-V transcript and protein expression. Overall, this study demonstrates that AR-Vs broadly restore AR chromatin binding events that are otherwise suppressed during endocrine therapy, and provides pre-clinical rationale for BET inhibition as a strategy for inhibiting expression and chromatin binding of AR-Vs in PCa.
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Affiliation(s)
- Siu Chiu Chan
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55905, USA
| | - Luke A Selth
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Mens' Health, School of Medicine, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Yingming Li
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55905, USA
| | - Michael D Nyquist
- Graduate Program in Molecular, Cellular, Developmental Biology and Genetics, University of Minnesota, Minneapolis, MN 55905, USA
| | - Lu Miao
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - James E Bradner
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Ganesh V Raj
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Wayne D Tilley
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Mens' Health, School of Medicine, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Scott M Dehm
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55905, USA Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55905, USA
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22
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Popovics P, Frigo DE, Schally AV, Rick FG. Targeting the 5'-AMP-activated protein kinase and related metabolic pathways for the treatment of prostate cancer. Expert Opin Ther Targets 2015; 19:617-32. [PMID: 25600663 DOI: 10.1517/14728222.2015.1005603] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Increasing evidence suggests that prostate cancer cells undergo unique metabolic reprogramming during transformation. A master regulator of cellular homeostasis, 5'-AMP-activated protein kinase (AMPK), directs metabolic adaptation that supports the growth demands of rapidly dividing cancer cells. The utilization of AMPK as a therapeutic target may therefore provide an effective strategy in the treatment of prostate cancer. AREAS COVERED Our review describes the regulation of AMPK by androgens and upstream kinases including the calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) in prostate cancer. Oncogenic, AMPK-regulated pathways that direct various metabolic processes are also addressed. Furthermore, we discuss the role of AMPK in growth arrest and autophagy as a potential survival pathway for cancer cells. In addition, by regulating non-metabolic pathways, AMPK may stimulate migration and mitosis. Finally, this review summarizes efforts to treat prostate cancer with pharmacological agents capable of modulating AMPK signaling. EXPERT OPINION Current research is primarily focused on developing drugs that activate AMPK as a treatment for prostate cancer. However, oncogenic aspects of AMPK signaling calls for caution about employing such therapies. We think that inhibitors of CaMKK2 or AMPK, or perhaps the modulation of downstream targets of AMPK, will gain importance in the clinical management of prostate cancer.
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Affiliation(s)
- Petra Popovics
- Veterans Affairs Medical Center and South Florida Veterans Affairs Foundation for Research and Education , Research (151) 2A127, 1201 NW 16th St, Miami, FL 33125 , USA +1 305 5753477 ; +1 305 5753126 ;
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23
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Munkley J, Lafferty NP, Kalna G, Robson CN, Leung HY, Rajan P, Elliott DJ. Androgen-regulation of the protein tyrosine phosphatase PTPRR activates ERK1/2 signalling in prostate cancer cells. BMC Cancer 2015; 15:9. [PMID: 25592066 PMCID: PMC4302442 DOI: 10.1186/s12885-015-1012-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 01/06/2015] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Androgens drive the onset and progression of prostate cancer (PCa) via androgen receptor (AR) signalling. The principal treatment for PCa is androgen deprivation therapy, although the majority of patients eventually develop a lethal castrate-resistant form of the disease, where despite low serum testosterone levels AR signalling persists. Advanced PCa often has hyper-activated RAS/ERK1/2 signalling thought to be due to loss of function of key negative regulators of the pathway, the details of which are not fully understood. METHODS We recently carried out a genome-wide study and identified a subset of 226 novel androgen-regulated genes (PLOS ONE 6:e29088, 2011). In this study we have meta-analysed this dataset with genes and pathways frequently mutated in PCa to identify androgen-responsive regulators of the RAS/ERK1/2 pathway. RESULTS We find the PTGER4 and TSPYL2 genes are up-regulated by androgen stimulation and the ADCY1, OPKR1, TRIB1, SPRY1 and PTPRR are down-regulated by androgens. Further characterisation of PTPRR protein in LNCaP cells revealed it is an early and direct target of the androgen receptor which negatively regulates the RAS/ERK1/2 pathway and reduces cell proliferation in response to androgens. CONCLUSION Our data suggest that loss of PTPRR in clinical PCa is one factor that might contribute to activation of the RAS/ERK1/2 pathway.
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Affiliation(s)
- Jennifer Munkley
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, NE1 3BZ, UK.
| | - Nicholas P Lafferty
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, NE1 3BZ, UK.
| | - Gabriela Kalna
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK.
| | - Craig N Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, NE2 4HH, UK.
| | - Hing Y Leung
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, G12 8QQ, UK.
| | - Prabhakar Rajan
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, G12 8QQ, UK.
| | - David J Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, NE1 3BZ, UK.
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