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Behrens K, Brajanovski N, Xu Z, Viney EM, DiRago L, Hediyeh-Zadeh S, Davis MJ, Pearson RB, Sanij E, Alexander WS, Ng AP. ERG and c-MYC regulate a critical gene network in BCR::ABL1-driven B cell acute lymphoblastic leukemia. SCIENCE ADVANCES 2024; 10:eadj8803. [PMID: 38457494 PMCID: PMC10923517 DOI: 10.1126/sciadv.adj8803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/31/2024] [Indexed: 03/10/2024]
Abstract
Philadelphia chromosome-positive B cell acute lymphoblastic leukemia (B-ALL), characterized by the BCR::ABL1 fusion gene, remains a poor prognosis cancer needing new therapeutic approaches. Transcriptomic profiling identified up-regulation of oncogenic transcription factors ERG and c-MYC in BCR::ABL1 B-ALL with ERG and c-MYC required for BCR::ABL1 B-ALL in murine and human models. Profiling of ERG- and c-MYC-dependent gene expression and analysis of ChIP-seq data established ERG and c-MYC coordinate a regulatory network in BCR::ABL1 B-ALL that controls expression of genes involved in several biological processes. Prominent was control of ribosome biogenesis, including expression of RNA polymerase I (POL I) subunits, the importance of which was validated by inhibition of BCR::ABL1 cells by POL I inhibitors, including CX-5461, that prevents promoter recruitment and transcription initiation by POL I. Our results reveal an essential ERG- and c-MYC-dependent transcriptional network involved in regulation of metabolic and ribosome biogenesis pathways in BCR::ABL1 B-ALL, from which previously unidentified vulnerabilities and therapeutic targets may emerge.
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Affiliation(s)
- Kira Behrens
- Blood Cells and Blood Cancer Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Natalie Brajanovski
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - Zhen Xu
- Blood Cells and Blood Cancer Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Elizabeth M. Viney
- Blood Cells and Blood Cancer Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Ladina DiRago
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Soroor Hediyeh-Zadeh
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Melissa J. Davis
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Clinical Pathology, University of Melbourne, Parkville, Australia
- The Diamantina Institute, The University of Queensland, Woolloongabba, Australia
- The South Australian Immunogenomics Cancer Institute, The University of Adelaide, Adelaide, Australia
| | - Richard B. Pearson
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Australia
| | - Elaine Sanij
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Australia
- St. Vincent’s Institute of Medical Research, Fitzroy, Australia
- Department of Medicine, St. Vincent’s Hospital, University of Melbourne, Parkville, Australia
| | - Warren S. Alexander
- Blood Cells and Blood Cancer Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Ashley P. Ng
- Department of Medical Biology, University of Melbourne, Parkville, Australia
- Immunology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
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Scull CE, Twa G, Zhang Y, Yang NJ, Hunter RN, Augelli-Szafran CE, Schneider DA. Small Molecule RBI2 Disrupts Ribosome Biogenesis through Pre-rRNA Depletion. Cancers (Basel) 2023; 15:3303. [PMID: 37444413 PMCID: PMC10340317 DOI: 10.3390/cancers15133303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Cancer cells are especially sensitive to perturbations in ribosome biogenesis as they rely on finely tuned protein homeostasis to facilitate their rapid growth and proliferation. While ribosome synthesis and cancer have a well-established relationship, ribosome biogenesis has only recently drawn interest as a cancer therapeutic target. In this study, we exploited the relationship between ribosome biogenesis and cancer cell proliferation by using a potent ribosome biogenesis inhibitor, RBI2 (Ribosome Biogenesis Inhibitor 2), to perturb cancer cell growth and viability. We demonstrate herein that RBI2 significantly decreases cell viability in malignant melanoma cells and breast cancer cell lines. Treatment with RBI2 dramatically and rapidly decreased ribosomal RNA (rRNA) synthesis, without affecting the occupancy of RNA polymerase I (Pol I) on the ribosomal DNA template. Next-generation RNA sequencing (RNA-seq) revealed that RBI2 and previously described ribosome biogenesis inhibitor CX-5461 induce distinct changes in the transcriptome. An investigation of the content of the pre-rRNAs through RT-qPCR revealed an increase in the polyadenylation of cellular rRNA after treatment with RBI2, constituting a known pathway by which rRNA degradation occurs. Northern blotting revealed that RBI2 does not appear to impair or alter rRNA processing. Collectively, these data suggest that RBI2 inhibits rRNA synthesis differently from other previously described ribosome biogenesis inhibitors, potentially acting through a novel pathway that upregulates the turnover of premature rRNAs.
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Affiliation(s)
- Catherine E. Scull
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Guy Twa
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yinfeng Zhang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Naiheng J. Yang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | | | - David A. Schneider
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Wong MRE, Lim KH, Hee EXY, Chen H, Kuick CH, Jet AS, Chang KTE, Sulaiman NS, Low SY, Hartono S, Tran ANT, Ahamed SH, Lam CMJ, Soh SY, Hannan KM, Hannan RD, Coupland LA, Loh AHP. Targeting Mutant Dicer Tumorigenesis in Pleuropulmonary Blastoma via Inhibition of RNA Polymerase I. Transl Res 2023:S1931-5244(23)00041-5. [PMID: 36921796 DOI: 10.1016/j.trsl.2023.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 02/23/2023] [Accepted: 03/07/2023] [Indexed: 03/14/2023]
Abstract
DICER1 mutations predispose to increased risk for various cancers, particularly pleuropulmonary blastoma (PPB), the commonest lung malignancy of childhood. There is a paucity of directly actionable molecular targets as these tumors are driven by loss-of-function mutations of DICER1. Therapeutic development for PPB is further limited by a lack of biologically and physiologically-representative disease models. Given recent evidence of Dicer's role as a haploinsufficient tumor suppressor regulating RNA polymerase I (Pol I), Pol I inhibition could abrogate mutant Dicer-mediated accumulation of stalled polymerases to trigger apoptosis. Hence, we developed a novel sub-pleural orthotopic PPB patient-derived xenograft (PDX) model that retained both RNase IIIa and IIIb hotspot mutations and recapitulated the cardiorespiratory physiology of intra-thoracic disease, and with it evaluated the tolerability and efficacy of first-in-class Pol I inhibitor CX-5461. In PDX tumors, CX-5461 significantly reduced H3K9 di-methylation and increased nuclear p53 expression, within 24 hours' exposure. Following treatment at the maximum tolerated dosing regimen (12 doses, 30mg/kg), tumors were smaller and less hemorrhagic than controls, with significantly decreased cellular proliferation, and increased apoptosis. As demonstrated in a novel intra-thoracic tumor model of PPB, Pol I inhibition with CX-5461 could be a tolerable and clinically-feasible therapeutic strategy for mutant Dicer tumors, inducing anti-tumor effects by decreasing H3K9 methylation and enhancing p53-mediated apoptosis.
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Affiliation(s)
- Megan Rui En Wong
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899
| | - Kia Hui Lim
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
| | - Esther Xuan Yi Hee
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899
| | - Huiyi Chen
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore 229899
| | - Chik Hong Kuick
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore 229899
| | - Aw Sze Jet
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore 229899
| | - Kenneth Tou En Chang
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899; Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore 229899; Duke-NUS School of Medicine, Singapore 169857
| | - Nurfarhanah Syed Sulaiman
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899; Department of Neurology, National Neuroscience Institute, Singapore 308433
| | - Sharon Yy Low
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899; Department of Neurology, National Neuroscience Institute, Singapore 308433; Duke-NUS School of Medicine, Singapore 169857
| | - Septian Hartono
- Department of Oncologic Imaging, National Cancer Centre Singapore, Singapore 169610
| | - Anh Nguyen Tuan Tran
- Department of Oncologic Imaging, National Cancer Centre Singapore, Singapore 169610
| | - Summaiyya Hanum Ahamed
- Duke-NUS School of Medicine, Singapore 169857; Department of Diagnostic and Interventional Imaging, KK Women's and Children's Hospital, Singapore 229899
| | - Ching Mei Joyce Lam
- Duke-NUS School of Medicine, Singapore 169857; Department of Paediatric Subspecialties Haematology/Oncology Service, KK Women's and Children's Hospital, Singapore 229899
| | - Shui Yen Soh
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899; Duke-NUS School of Medicine, Singapore 169857; Department of Paediatric Subspecialties Haematology/Oncology Service, KK Women's and Children's Hospital, Singapore 229899
| | - Katherine M Hannan
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, the Australian National University, Canberra, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Ross D Hannan
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, the Australian National University, Canberra, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Lucy A Coupland
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, the Australian National University, Canberra, Australia
| | - Amos Hong Pheng Loh
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, Children's Blood and Cancer Centre, KK Women's and Children's Hospital, Singapore 229899; Duke-NUS School of Medicine, Singapore 169857; Department of Paediatric Surgery, KK Women's and Children's Hospital, Singapore 229899.
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4
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How to Shut Down Transcription in Archaea during Virus Infection. Microorganisms 2022; 10:microorganisms10091824. [PMID: 36144426 PMCID: PMC9501531 DOI: 10.3390/microorganisms10091824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/09/2022] [Accepted: 09/10/2022] [Indexed: 11/16/2022] Open
Abstract
Multisubunit RNA polymerases (RNAPs) carry out transcription in all domains of life; during virus infection, RNAPs are targeted by transcription factors encoded by either the cell or the virus, resulting in the global repression of transcription with distinct outcomes for different host–virus combinations. These repressors serve as versatile molecular probes to study RNAP mechanisms, as well as aid the exploration of druggable sites for the development of new antibiotics. Here, we review the mechanisms and structural basis of RNAP inhibition by the viral repressor RIP and the crenarchaeal negative regulator TFS4, which follow distinct strategies. RIP operates by occluding the DNA-binding channel and mimicking the initiation factor TFB/TFIIB. RIP binds tightly to the clamp and locks it into one fixed position, thereby preventing conformational oscillations that are critical for RNAP function as it progresses through the transcription cycle. TFS4 engages with RNAP in a similar manner to transcript cleavage factors such as TFS/TFIIS through the NTP-entry channel; TFS4 interferes with the trigger loop and bridge helix within the active site by occlusion and allosteric mechanisms, respectively. The conformational changes in RNAP described above are universally conserved and are also seen in inactive dimers of eukaryotic RNAPI and several inhibited RNAP complexes of both bacterial and eukaryotic RNA polymerases, including inactive states that precede transcription termination. A comparison of target sites and inhibitory mechanisms reveals that proteinaceous repressors and RNAP-specific antibiotics use surprisingly common ways to inhibit RNAP function.
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Tsoi H, You CP, Leung MH, Man EPS, Khoo US. Targeting Ribosome Biogenesis to Combat Tamoxifen Resistance in ER+ve Breast Cancer. Cancers (Basel) 2022; 14:cancers14051251. [PMID: 35267559 PMCID: PMC8909264 DOI: 10.3390/cancers14051251] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/24/2022] [Accepted: 02/27/2022] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Resistance to tamoxifen treatment is an obstacle for ER+ve breast cancer therapy. The overexpression of c-MYC is a known driver of cancer progression and is associated with tamoxifen resistance. Through mediating the up-regulation of ribosome biogenesis and alteration of the transcriptome, c-MYC modulates the translation profile to facilitate the development of tamoxifen resistance. c-MYC is, however, undruggable. Thus, targeting downstream mechanisms mediated by c-MYC might be a more feasible approach. Studies have demonstrated that inhibition of ribosome biogenesis can achieve tumour suppression. Targeting ribosome biogenesis may thus be a feasible strategy to reverse tamoxifen resistance. This article reviews the current evidence to support the feasibility of suppressing ribosome biogenesis to reverse tamoxifen resistance in ER+ve breast cancer. Abstract Breast cancer is a heterogeneous disease. Around 70% of breast cancers are estrogen receptor-positive (ER+ve), with tamoxifen being most commonly used as an adjuvant treatment to prevent recurrence and metastasis. However, half of the patients will eventually develop tamoxifen resistance. The overexpression of c-MYC can drive the development of ER+ve breast cancer and confer tamoxifen resistance through multiple pathways. One key mechanism is to enhance ribosome biogenesis, synthesising mature ribosomes. The over-production of ribosomes sustains the demand for proteins necessary to maintain a high cell proliferation rate and combat apoptosis induced by therapeutic agents. c-MYC overexpression can induce the expression of eIF4E that favours the translation of structured mRNA to produce oncogenic factors that promote cell proliferation and confer tamoxifen resistance. Either non-phosphorylated or phosphorylated eIF4E can mediate such an effect. Since ribosomes play an essential role in c-MYC-mediated cancer development, suppressing ribosome biogenesis may help reduce aggressiveness and reverse tamoxifen resistance in breast cancer. CX-5461, CX-3543 and haemanthamine have been shown to repress ribosome biogenesis. Using these chemicals might help reverse tamoxifen resistance in ER+ve breast cancer, provided that c-MYC-mediated ribosome biogenesis is the crucial factor for tamoxifen resistance. To employ these ribosome biogenesis inhibitors to combat tamoxifen resistance in the future, identification of predictive markers will be necessary.
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6
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Kang CW, Hannan KM, Blackburn AC, Loh AHP, Hong KC, Yuan GJ, Hein N, Drygin D, Hannan RD, Coupland LA. The therapeutic potential of RNA Polymerase I transcription inhibitor, CX-5461, in uterine leiomyosarcoma. Invest New Drugs 2022; 40:529-536. [PMID: 35201535 PMCID: PMC9098598 DOI: 10.1007/s10637-022-01222-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 02/07/2022] [Indexed: 12/01/2022]
Abstract
Background. Uterine leiomyosarcoma is a rare aggressive smooth muscle cancer with poor survival rates. RNA Polymerase I (Pol I) activity is elevated in many cancers supporting tumour growth and prior studies in uterine leiomyosarcoma revealed enlarged nucleoli and upregulated Pol I activity-related genes. This study aimed to investigate the anti-tumour potential of CX-5461, a Pol I transcription inhibitor currently being evaluated in clinical trials for several cancers, against the human uterine leiomyosarcoma cell line, SK-UT-1. Methods. SK-UT-1 was characterised using genome profiling and western blotting. The anti-tumour effects of CX-5461 were investigated using cell proliferation assays, expression analysis using qRT-PCR, and BrdU/PI based cell cycle analysis. Results. Genetic analysis of SK-UT-1 revealed mutations in TP53, RB1, PTEN, APC and TSC1 & 2, all potentially associated with increased Pol I activity. Protein expression analysis showed dysregulated p53, RB1 and c-Myc. CX-5461 treatment resulted in an anti-proliferation response, G2 phase cell-cycle arrest and on-target activity demonstrated by reduced ribosomal DNA transcription. Conclusions. SK-UT-1 was confirmed as a representative model of uterine leiomyosarcoma and CX-5461 has significant potential as a novel adjuvant for this rare cancer.
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Affiliation(s)
- Chang-Won Kang
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Katherine M Hannan
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, 3010, Australia
| | - Anneke C Blackburn
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Amos H P Loh
- VIVA-KKH Paediatric Brain and Solid Tumour Programme, KK Women's and Children's Hospital, Bukit Timah, Singapore
| | - Kuick Chik Hong
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Bukit Timah, Singapore
| | - Goh Jian Yuan
- Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Bukit Timah, Singapore
| | - Nadine Hein
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Denis Drygin
- Regulus Therapeutics, 4224 Campus Point C, San Diego, CA, USA
| | - Ross D Hannan
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, 3010, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, 3800, Australia.,School of Biomedical Sciences, University of Queensland, 4067, St Lucia, Australia
| | - Lucy A Coupland
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.
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Chang CYY, Chiang AJ, Yan MJ, Lai MT, Su YY, Huang HY, Chang CY, Li YH, Li PF, Chen CM, Hwang T, Hogg C, Greaves E, Sheu JJC. Ribosome Biogenesis Serves as a Therapeutic Target for Treating Endometriosis and the Associated Complications. Biomedicines 2022; 10:biomedicines10010185. [PMID: 35052864 PMCID: PMC8774031 DOI: 10.3390/biomedicines10010185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/01/2022] [Accepted: 01/13/2022] [Indexed: 12/10/2022] Open
Abstract
Ribosome biogenesis is a cellular process critical for protein homeostasis during cell growth and multiplication. Our previous study confirmed up-regulation of ribosome biogenesis during endometriosis progression and malignant transition, thus anti-ribosome biogenesis may be effective for treating endometriosis and the associated complications. A mouse model with human endometriosis features was established and treated with three different drugs that can block ribosome biogenesis, including inhibitors against mTOR/PI3K (GSK2126458) and RNA polymerase I (CX5461 and BMH21). The average lesion numbers and disease frequencies were significantly reduced in treated mice as compared to controls treated with vehicle. Flow cytometry analyses confirmed the reduction of small peritoneal macrophage and neutrophil populations with increased large versus small macrophage ratios, suggesting inflammation suppression by drug treatments. Lesions in treated mice also showed lower nerve fiber density which can support the finding of pain-relief by behavioral studies. Our study therefore suggested ribosome biogenesis as a potential therapeutic target for treating endometriosis.
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Affiliation(s)
- Cherry Yin-Yi Chang
- Department of Obstetrics and Gynecology, China Medical University Hospital, Taichung 404332, Taiwan;
- Department of Medicine, School of Medicine, China Medical University, Taichung 404333, Taiwan
| | - An-Jen Chiang
- Department of Obstetrics and Gynecology, Kaohsiung Veterans General Hospital, Kaohsiung 813414, Taiwan;
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Man-Ju Yan
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Ming-Tsung Lai
- Department of Pathology, Taichung Hospital, Ministry of Health and Welfare, Taichung 403301, Taiwan;
| | - Yun-Yi Su
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Hsin-Yi Huang
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Chan-Yu Chang
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Ya-Hui Li
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Pei-Fen Li
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Chih-Mei Chen
- Human Genetic Center, China Medical University Hospital, Taichung 404332, Taiwan;
| | - Tritium Hwang
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
| | - Chloe Hogg
- Medical Research Council Centre for Reproductive Health, The University of Edinburgh, Edinburgh EH16 4TJ, UK;
| | - Erin Greaves
- Centre for Early Life, Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
- Correspondence: (E.G.); (J.J.-C.S.)
| | - Jim Jinn-Chyuan Sheu
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan; (M.-J.Y.); (Y.-Y.S.); (H.-Y.H.); (C.-Y.C.); (Y.-H.L.); (P.-F.L.); (T.H.)
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807378, Taiwan
- Institute of Biopharmaceutical Sciences, National Sun Yat-sen University, Kaohsiung 804201, Taiwan
- Institute of Precision Medicine, National Sun Yat-sen University, Kaohsiung 804201, Taiwan
- Correspondence: (E.G.); (J.J.-C.S.)
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8
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Bowry A, Kelly RDW, Petermann E. Hypertranscription and replication stress in cancer. Trends Cancer 2021; 7:863-877. [PMID: 34052137 DOI: 10.1016/j.trecan.2021.04.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/23/2021] [Accepted: 04/30/2021] [Indexed: 12/18/2022]
Abstract
Replication stress results from obstacles to replication fork progression, including ongoing transcription, which can cause transcription-replication conflicts. Oncogenic signaling can promote global increases in transcription activity, also termed hypertranscription. Despite the widely accepted importance of oncogene-induced hypertranscription, its study remains neglected compared with other causes of replication stress and genomic instability in cancer. A growing number of recent studies are reporting that oncogenes, such as RAS, and targeted cancer treatments, such as bromodomain and extraterminal motif (BET) bromodomain inhibitors, increase global transcription, leading to R-loop accumulation, transcription-replication conflicts, and the activation of replication stress responses. Here we discuss our mechanistic understanding of hypertranscription-induced replication stress and the resulting cellular responses, in the context of oncogenes and targeted cancer therapies.
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Affiliation(s)
- Akhil Bowry
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Richard D W Kelly
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
| | - Eva Petermann
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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9
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Kang J, Brajanovski N, Chan KT, Xuan J, Pearson RB, Sanij E. Ribosomal proteins and human diseases: molecular mechanisms and targeted therapy. Signal Transduct Target Ther 2021; 6:323. [PMID: 34462428 PMCID: PMC8405630 DOI: 10.1038/s41392-021-00728-8] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/12/2021] [Accepted: 07/30/2021] [Indexed: 02/07/2023] Open
Abstract
Ribosome biogenesis and protein synthesis are fundamental rate-limiting steps for cell growth and proliferation. The ribosomal proteins (RPs), comprising the structural parts of the ribosome, are essential for ribosome assembly and function. In addition to their canonical ribosomal functions, multiple RPs have extra-ribosomal functions including activation of p53-dependent or p53-independent pathways in response to stress, resulting in cell cycle arrest and apoptosis. Defects in ribosome biogenesis, translation, and the functions of individual RPs, including mutations in RPs have been linked to a diverse range of human congenital disorders termed ribosomopathies. Ribosomopathies are characterized by tissue-specific phenotypic abnormalities and higher cancer risk later in life. Recent discoveries of somatic mutations in RPs in multiple tumor types reinforce the connections between ribosomal defects and cancer. In this article, we review the most recent advances in understanding the molecular consequences of RP mutations and ribosomal defects in ribosomopathies and cancer. We particularly discuss the molecular basis of the transition from hypo- to hyper-proliferation in ribosomopathies with elevated cancer risk, a paradox termed "Dameshek's riddle." Furthermore, we review the current treatments for ribosomopathies and prospective therapies targeting ribosomal defects. We also highlight recent advances in ribosome stress-based cancer therapeutics. Importantly, insights into the mechanisms of resistance to therapies targeting ribosome biogenesis bring new perspectives into the molecular basis of cancer susceptibility in ribosomopathies and new clinical implications for cancer therapy.
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Affiliation(s)
- Jian Kang
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC Australia
| | - Natalie Brajanovski
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia
| | - Keefe T. Chan
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC Australia
| | - Jiachen Xuan
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC Australia
| | - Richard B. Pearson
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC Australia ,grid.1002.30000 0004 1936 7857Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC Australia ,grid.1008.90000 0001 2179 088XDepartment of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, VIC Australia
| | - Elaine Sanij
- grid.1055.10000000403978434Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XSir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC Australia ,grid.1008.90000 0001 2179 088XDepartment of Clinical Pathology, University of Melbourne, Melbourne, VIC Australia ,grid.1073.50000 0004 0626 201XSt. Vincent’s Institute of Medical Research, Fitzroy, VIC Australia
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10
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The functional GRHL3-filaggrin axis maintains a tumor differentiation potential and influences drug sensitivity. Mol Ther 2021; 29:2571-2582. [PMID: 33775911 PMCID: PMC8353142 DOI: 10.1016/j.ymthe.2021.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/06/2021] [Accepted: 03/22/2021] [Indexed: 12/20/2022] Open
Abstract
Current therapies for treating heterogeneous cancers such as head and neck squamous cell carcinoma (HNSCC) are non-selective and are administered independent of response biomarkers. Therapy resistance subsequently emerges, resulting in increased cellular proliferation that is associated with loss of differentiation. Whether a cancer cell differentiation potential can dictate therapy responsiveness is still currently unknown. A multi-omic approach integrating whole-genome and whole-transcriptome sequencing with drug sensitivity was employed in a HNSCC mouse model, primary patients’ data, and human cell lines to assess the potential of functional differentiation in predicting therapy response. Interestingly, a subset of HNSCC with effective GRHL3-dependent differentiation was the most sensitive to inhibitors of PI3K/mTOR, c-Myc, and STAT3 signaling. Furthermore, we identified the GRHL3-differentiation target gene Filaggrin (FLG) as a response biomarker and more importantly, stratified HNSCC subsets as treatment resistant based on their FLG mutational profile. The loss of FLG in sensitive HNSCC resulted in a dramatic resistance to targeted therapies while the GRHL3-FLG signature predicted a favorable patient prognosis. This study provides evidence for a functional GRHL3-FLG tumor-specific differentiation axis that regulates targeted therapy response in HNSCC and establishes a rationale for clinical investigation of differentiation-paired targeted therapy in heterogeneous cancers.
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11
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Figueiredo VC, McCarthy JJ. Targeting cancer via ribosome biogenesis: the cachexia perspective. Cell Mol Life Sci 2021; 78:5775-5787. [PMID: 34196731 PMCID: PMC11072391 DOI: 10.1007/s00018-021-03888-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/03/2021] [Accepted: 06/18/2021] [Indexed: 12/14/2022]
Abstract
Cancer cachexia afflicts many advanced cancer patients with many progressing to death. While there have been many advancements in understanding the molecular mechanisms that contribute to the development of cancer cachexia, substantial gaps still exist. Chemotherapy drugs often target ribosome biogenesis to slow or blunt tumor cell growth and proliferation. Some of the most frequent side-effects of chemotherapy are loss of skeletal muscle mass, muscular strength and an increase in fatigue. Given that ribosome biogenesis has emerged as a main mechanism regulating muscle hypertrophy, and more recently, also implicated in muscle atrophy, we propose that some chemotherapy drugs can cause further muscle wasting via its effect on skeletal muscle cells. Many chemotherapy drugs, including the most prescribed drugs such as doxorubicin and cisplatin, affect ribosomal DNA transcription, or other pathways related to ribosome biogenesis. Furthermore, middle-aged and older individuals are the most affected population with cancer, and advanced cancer patients often show reduced levels of physical inactivity. Thus, aging and inactivity can themselves affect muscle ribosome biogenesis, which can further worsen the effect of chemotherapy on skeletal muscle ribosome biogenesis and, ultimately, muscle mass and function. We propose that chemotherapy can accelerate the onset or worsen cancer cachexia via its inhibitory effects on skeletal muscle ribosome biogenesis. We end our review by providing recommendations that could be used to ameliorate the negative effects of chemotherapy on skeletal muscle ribosome biogenesis.
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Affiliation(s)
- Vandré Casagrande Figueiredo
- College of Health Sciences, University of Kentucky, Lexington, KY, USA.
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
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12
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Antagonising Chromatin Remodelling Activities in the Regulation of Mammalian Ribosomal Transcription. Genes (Basel) 2021; 12:genes12070961. [PMID: 34202617 PMCID: PMC8303148 DOI: 10.3390/genes12070961] [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: 05/24/2021] [Revised: 06/16/2021] [Accepted: 06/19/2021] [Indexed: 12/29/2022] Open
Abstract
Ribosomal transcription constitutes the major energy consuming process in cells and is regulated in response to proliferation, differentiation and metabolic conditions by several signalling pathways. These act on the transcription machinery but also on chromatin factors and ncRNA. The many ribosomal gene repeats are organised in a number of different chromatin states; active, poised, pseudosilent and repressed gene repeats. Some of these chromatin states are unique to the 47rRNA gene repeat and do not occur at other locations in the genome, such as the active state organised with the HMG protein UBF whereas other chromatin state are nucleosomal, harbouring both active and inactive histone marks. The number of repeats in a certain state varies on developmental stage and cell type; embryonic cells have more rRNA gene repeats organised in an open chromatin state, which is replaced by heterochromatin during differentiation, establishing different states depending on cell type. The 47S rRNA gene transcription is regulated in different ways depending on stimulus and chromatin state of individual gene repeats. This review will discuss the present knowledge about factors involved, such as chromatin remodelling factors NuRD, NoRC, CSB, B-WICH, histone modifying enzymes and histone chaperones, in altering gene expression and switching chromatin states in proliferation, differentiation, metabolic changes and stress responses.
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13
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Wood S, Willbanks A, Cheng JX. The Role of RNA Modifications and RNA-modifying Proteins in Cancer Therapy and Drug Resistance. Curr Cancer Drug Targets 2021; 21:326-352. [PMID: 33504307 DOI: 10.2174/1568009621666210127092828] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 11/22/2022]
Abstract
The advent of new genome-wide sequencing technologies has uncovered abnormal RNA modifications and RNA editing in a variety of human cancers. The discovery of reversible RNA N6-methyladenosine (RNA: m6A) by fat mass and obesity-associated protein (FTO) demethylase has led to exponential publications on the pathophysiological functions of m6A and its corresponding RNA modifying proteins (RMPs) in the past decade. Some excellent reviews have summarized the recent progress in this field. Compared to the extent of research into RNA: m6A and DNA 5-methylcytosine (DNA: m5C), much less is known about other RNA modifications and their associated RMPs, such as the role of RNA: m5C and its RNA cytosine methyltransferases (RCMTs) in cancer therapy and drug resistance. In this review, we will summarize the recent progress surrounding the function, intramolecular distribution and subcellular localization of several major RNA modifications, including 5' cap N7-methylguanosine (m7G) and 2'-O-methylation (Nm), m6A, m5C, A-to-I editing, and the associated RMPs. We will then discuss dysregulation of those RNA modifications and RMPs in cancer and their role in cancer therapy and drug resistance.
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Affiliation(s)
- Shaun Wood
- Department of Pathology, Hematopathology Section, University of Chicago, Chicago, IL60637, United States
| | - Amber Willbanks
- Department of Pathology, Hematopathology Section, University of Chicago, Chicago, IL60637, United States
| | - Jason X Cheng
- Department of Pathology, Hematopathology Section, University of Chicago, Chicago, IL60637, United States
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14
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Ladelfa MF, Peche LY, Amato GE, Escalada MC, Zampieri S, Pascucci FA, Benevento AF, Do Porto DF, Dardis A, Schneider C, Monte M. Expression of the tumor-expressed protein MageB2 enhances rRNA transcription. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119015. [PMID: 33741433 DOI: 10.1016/j.bbamcr.2021.119015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 02/22/2021] [Accepted: 03/12/2021] [Indexed: 11/17/2022]
Abstract
An essential requirement for cells to sustain a high proliferating rate is to be paired with enhanced protein synthesis through the production of ribosomes. For this reason, part of the growth-factor signaling pathways, are devoted to activate ribosome biogenesis. Enhanced production of ribosomes is a hallmark in cancer cells, which is boosted by different mechanisms. Here we report that the nucleolar tumor-protein MageB2, whose expression is associated with cell proliferation, also participates in ribosome biogenesis. Studies carried out in both siRNA-mediated MageB2 silenced cells and CRISPR/CAS9-mediated MageB2 knockout (KO) cells showed that its expression is linked to rRNA transcription increase independently of the cell proliferation status. Mechanistically, MageB2 interacts with phospho-UBF, a protein which causes the recruitment of RNA Pol I pre-initiation complex required for rRNA transcription. In addition, cells expressing MageB2 displays enhanced phospho-UBF occupancy at the rDNA gene promoter. Proteomic studies performed in MageB2 KO cells revealed impairment in ribosomal protein (RPs) content. Functionally, enhancement in rRNA production in MageB2 expressing cells, was directly associated with an increased dynamic in protein synthesis. Altogether our results unveil a novel function for a tumor-expressed protein from the MAGE-I family. Findings reported here suggest that nucleolar MageB2 might play a role in enhancing ribosome biogenesis as part of its repertoire to support cancer cell proliferation.
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Affiliation(s)
- María Fátima Ladelfa
- Lab. Oncología Molecular, Departamento de Química Biológica, IQUIBICEN-UBA/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Leticia Yamila Peche
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie, Area Science Park, Trieste, Italy
| | - Gastón Ezequiel Amato
- Lab. Oncología Molecular, Departamento de Química Biológica, IQUIBICEN-UBA/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Micaela Carolina Escalada
- Lab. Oncología Molecular, Departamento de Química Biológica, IQUIBICEN-UBA/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Stefania Zampieri
- Centro di Coordinamento Regionale per le Malattie Rare, Ospedale Universitario Santa Maria Della Misericordia, Udine, Italy
| | - Franco Andrés Pascucci
- Lab. Oncología Molecular, Departamento de Química Biológica, IQUIBICEN-UBA/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Andres Fernandez Benevento
- Plataforma de Bioinformática Argentina, Instituto de Cálculo, Pabellón 2, Ciudad Universitaria, Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires, Argentina
| | - Dario Fernandez Do Porto
- Plataforma de Bioinformática Argentina, Instituto de Cálculo, Pabellón 2, Ciudad Universitaria, Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires, Argentina
| | - Andrea Dardis
- Centro di Coordinamento Regionale per le Malattie Rare, Ospedale Universitario Santa Maria Della Misericordia, Udine, Italy
| | - Claudio Schneider
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie, Area Science Park, Trieste, Italy; Dipartimento di Scienze e Tecnologie Biomediche, Università di Udine, p.le Kolbe 4, Udine, Italy
| | - Martin Monte
- Lab. Oncología Molecular, Departamento de Química Biológica, IQUIBICEN-UBA/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
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15
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Scull CE, Lucius AL, Schneider DA. The N-terminal domain of the A12.2 subunit stimulates RNA polymerase I transcription elongation. Biophys J 2021; 120:1883-1893. [PMID: 33737158 DOI: 10.1016/j.bpj.2021.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 01/26/2021] [Accepted: 03/09/2021] [Indexed: 11/30/2022] Open
Abstract
Eukaryotes express three DNA-dependent RNA polymerases (Pols) that are responsible for the entirety of cellular genomic expression. The three Pols have evolved to express specific cohorts of RNAs and thus have diverged both structurally and functionally to efficiently execute their specific transcriptional roles. One example of this divergence is Pol I's inclusion of a proofreading factor as a bona fide subunit, as opposed to Pol II, which recruits a transcription factor, TFIIS, for proofreading. The A12.2 (A12) subunit of Pol I shares homology with both the Rpb9 subunit of Pol II as well as the transcription factor TFIIS, which promotes RNA cleavage and proofreading by Pol II. In this study, the functional contribution of the TFIIS-like C-terminal domain and the Rpb9-like N-terminal domain of the A12 subunit are probed through mutational analysis. We found that a Pol I mutant lacking the C-terminal domain of the A12 subunit (ΔA12CTD Pol I) is slightly faster than wild-type Pol I in single-nucleotide addition, but ΔA12CTD Pol I lacks RNA cleavage activity. ΔA12CTD Pol I is likewise similar to wild-type Pol I in elongation complex stability, whereas removal of the entire A12 subunit (ΔA12 Pol I) was previously demonstrated to stabilize transcription elongation complexes. Furthermore, the ΔA12CTD Pol I is sensitive to downstream sequence context, as ΔA12CTD Pol I exposed to AT-rich downstream DNA is more arrest prone than ΔA12 Pol I. These data demonstrate that the N-terminal domain of A12 does not stimulate Pol I intrinsic RNA cleavage activity, but rather contributes to core transcription elongation properties of Pol I.
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Affiliation(s)
- Catherine E Scull
- The Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama
| | - Aaron L Lucius
- the Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama
| | - David A Schneider
- The Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama.
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16
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Patriarca A, Gaidano G. Investigational drugs for the treatment of diffuse large B-cell lymphoma. Expert Opin Investig Drugs 2020; 30:25-38. [PMID: 33295827 DOI: 10.1080/13543784.2021.1855140] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Introduction: Diffuse large B cell lymphoma (DLBCL) is the most frequent lymphoma in adults. 30-40% DLBCL eventually relapse and 10% are primary refractory, posing an unmet clinical need, especially in patients not eligible for hematopoietic stem cell transplant. Knowledge of DLBCL molecular pathogenesis has identified druggable molecular pathways. Surface antigens can be targeted by novel antibodies and innovative cell therapies. Areas covered: This review illuminates those investigational drugs and cell therapies that are currently in early phase clinical trials for the treatment of DLBCL. New small molecules that modulate the pathways involved in the molecular pathogenesis of DLBCL, monospecific and bispecific monoclonal antibodies, drug-immunoconjugates, and cellular therapies are placed under the spotlight. A futuristic perspective concludes the paper. Expert opinion: A precision medicine strategy based on robust molecular predictors of outcome is desirable in the development of investigational small molecules for DLBCL. Novel monoclonal and bispecific antibodies may be offered to (i) relapsed/refractory patients ineligible for CAR-T cells because of comorbidities, and (ii) younger patients before CAR-T cell infusion to reduce a high tumor burden. A focus on the optimal sequencing of the emerging DLBCL drugs is appropriate and necessary.
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Affiliation(s)
- Andrea Patriarca
- Division of Hematology, Department of Translational Medicine, Università Del Piemonte Orientale and Ospedale Maggiore Della Carità , Novara, Italy
| | - Gianluca Gaidano
- Division of Hematology, Department of Translational Medicine, Università Del Piemonte Orientale and Ospedale Maggiore Della Carità , Novara, Italy
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17
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Nait Slimane S, Marcel V, Fenouil T, Catez F, Saurin JC, Bouvet P, Diaz JJ, Mertani HC. Ribosome Biogenesis Alterations in Colorectal Cancer. Cells 2020; 9:E2361. [PMID: 33120992 PMCID: PMC7693311 DOI: 10.3390/cells9112361] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/24/2022] Open
Abstract
Many studies have focused on understanding the regulation and functions of aberrant protein synthesis in colorectal cancer (CRC), leaving the ribosome, its main effector, relatively underappreciated in CRC. The production of functional ribosomes is initiated in the nucleolus, requires coordinated ribosomal RNA (rRNA) processing and ribosomal protein (RP) assembly, and is frequently hyperactivated to support the needs in protein synthesis essential to withstand unremitting cancer cell growth. This elevated ribosome production in cancer cells includes a strong alteration of ribosome biogenesis homeostasis that represents one of the hallmarks of cancer cells. None of the ribosome production steps escape this cancer-specific dysregulation. This review summarizes the early and late steps of ribosome biogenesis dysregulations described in CRC cell lines, intestinal organoids, CRC stem cells and mouse models, and their possible clinical implications. We highlight how this cancer-related ribosome biogenesis, both at quantitative and qualitative levels, can lead to the synthesis of ribosomes favoring the translation of mRNAs encoding hyperproliferative and survival factors. We also discuss whether cancer-related ribosome biogenesis is a mere consequence of cancer progression or is a causal factor in CRC, and how altered ribosome biogenesis pathways can represent effective targets to kill CRC cells. The association between exacerbated CRC cell growth and alteration of specific steps of ribosome biogenesis is highlighted as a key driver of tumorigenesis, providing promising perspectives for the implementation of predictive biomarkers and the development of new therapeutic drugs.
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Affiliation(s)
- Sophie Nait Slimane
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Virginie Marcel
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Tanguy Fenouil
- Institute of Pathology EST, Hospices Civils de Lyon, Site-Est Groupement Hospitalier- Est, 69677 Bron, France;
| | - Frédéric Catez
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Jean-Christophe Saurin
- Gastroenterology and Genetic Department, Edouard Herriot Hospital, Hospices Civils de Lyon, 69008 Lyon, France;
| | - Philippe Bouvet
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Jean-Jacques Diaz
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
| | - Hichem C. Mertani
- Cancer Initiation and Tumor Cell Identity, Cancer Research Center of Lyon, Université de Lyon, Université Claude Bernard Lyon 1, Inserm U1052, CNRS UMR5286 Centre Léon Bérard, 69008 Lyon, France; (S.N.S.); (V.M.); (F.C.); (P.B.)
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18
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Xuan J, Pearson RB, Sanij E. CX-5461 can destabilize replication forks in PARP inhibitor-resistant models of ovarian cancer. Mol Cell Oncol 2020; 7:1805256. [PMID: 33235908 PMCID: PMC7671053 DOI: 10.1080/23723556.2020.1805256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Acquired drug resistance leads to poor clinical outcome in high grade serous ovarian cancer (HGSOC). We have demonstrated the efficacy of the novel drug CX-5461 in HGSOC is mediated through destabilization of DNA replication forks. The data highlights the potential of CX-5461 in overcoming a general mechanism of chemotherapeutic resistance.
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Affiliation(s)
- Jiachen Xuan
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia
| | - Richard B Pearson
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Australia
| | - Elaine Sanij
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia.,Department of Clinical Pathology, University of Melbourne, Parkville, Australia
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19
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Son J, Hannan KM, Poortinga G, Hein N, Cameron DP, Ganley ARD, Sheppard KE, Pearson RB, Hannan RD, Sanij E. rDNA Chromatin Activity Status as a Biomarker of Sensitivity to the RNA Polymerase I Transcription Inhibitor CX-5461. Front Cell Dev Biol 2020; 8:568. [PMID: 32719798 PMCID: PMC7349920 DOI: 10.3389/fcell.2020.00568] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 06/15/2020] [Indexed: 12/13/2022] Open
Abstract
Hyperactivation of RNA polymerase I (Pol I) transcription of ribosomal RNA (rRNA) genes (rDNA) is a key determinant of growth and proliferation and a consistent feature of cancer cells. We have demonstrated that inhibition of rDNA transcription by the Pol I transcription inhibitor CX-5461 selectively kills tumor cells in vivo. Moreover, the first-in human trial of CX-5461 has demonstrated CX-5461 is well-tolerated in patients and has single-agent anti-tumor activity in hematologic malignancies. However, the mechanisms underlying tumor cell sensitivity to CX-5461 remain unclear. Understanding these mechanisms is crucial for the development of predictive biomarkers of response that can be utilized for stratifying patients who may benefit from CX-5461. The rDNA repeats exist in four different and dynamic chromatin states: inactive rDNA can be either methylated silent or unmethylated pseudo-silent; while active rDNA repeats are described as either transcriptionally competent but non-transcribed or actively transcribed, depending on the level of rDNA promoter methylation, loading of the essential rDNA chromatin remodeler UBF and histone marks status. In addition, the number of rDNA repeats per human cell can reach hundreds of copies. Here, we tested the hypothesis that the number and/or chromatin status of the rDNA repeats, is a critical determinant of tumor cell sensitivity to Pol I therapy. We systematically examined a panel of ovarian cancer (OVCA) cell lines to identify rDNA chromatin associated biomarkers that might predict sensitivity to CX-5461. We demonstrated that an increased proportion of active to inactive rDNA repeats, independent of rDNA copy number, determines OVCA cell line sensitivity to CX-5461. Further, using zinc finger nuclease genome editing we identified that reducing rDNA copy number leads to an increase in the proportion of active rDNA repeats and confers sensitivity to CX-5461 but also induces genome-wide instability and sensitivity to DNA damage. We propose that the proportion of active to inactive rDNA repeats may serve as a biomarker to identify cancer patients who will benefit from CX-5461 therapy in future clinical trials. The data also reinforces the notion that rDNA instability is a threat to genomic integrity and cellular homeostasis.
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Affiliation(s)
- Jinbae Son
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
| | - Katherine M. Hannan
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Gretchen Poortinga
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
- Department of Medicine, St. Vincent’s Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Nadine Hein
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Donald P. Cameron
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Austen R. D. Ganley
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
| | - Karen E. Sheppard
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Richard B. Pearson
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Ross D. Hannan
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Elaine Sanij
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, Australia
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20
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Zaytseva O, Mitchell NC, Guo L, Marshall OJ, Parsons LM, Hannan RD, Levens DL, Quinn LM. Transcriptional repression of Myc underlies the tumour suppressor function of AGO1 in Drosophila. Development 2020; 147:147/11/dev190231. [PMID: 32527935 PMCID: PMC7295588 DOI: 10.1242/dev.190231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 04/27/2020] [Indexed: 12/29/2022]
Abstract
Here, we report novel tumour suppressor activity for the Drosophila Argonaute family RNA-binding protein AGO1, a component of the miRNA-dependent RNA-induced silencing complex (RISC). The mechanism for growth inhibition does not, however, involve canonical roles as part of the RISC; rather, AGO1 controls cell and tissue growth by functioning as a direct transcriptional repressor of the master regulator of growth, Myc. AGO1 depletion in wing imaginal discs drives a significant increase in ribosome biogenesis, nucleolar expansion and cell growth in a manner dependent on Myc abundance. Moreover, increased Myc promoter activity and elevated Myc mRNA in AGO1-depleted animals requires RNA polymerase II transcription. Further support for transcriptional AGO1 functions is provided by physical interaction with the RNA polymerase II transcriptional machinery (chromatin remodelling factors and Mediator Complex), punctate nuclear localisation in euchromatic regions and overlap with Polycomb Group transcriptional silencing loci. Moreover, significant AGO1 enrichment is observed on the Myc promoter and AGO1 interacts with the Myc transcriptional activator Psi. Together, our data show that Drosophila AGO1 functions outside of the RISC to repress Myc transcription and inhibit developmental cell and tissue growth. This article has an associated ‘The people behind the papers’ interview. Highlighted Article: In the Drosophila wing, the Argonaute family protein AGO1 acts independently of the miRNA-silencing pathway to restrict tissue growth by directly repressing transcription of the master growth regulator Myc.
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Affiliation(s)
- Olga Zaytseva
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia
| | - Naomi C Mitchell
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia
| | - Linna Guo
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia
| | | | | | - Ross D Hannan
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia
| | - David L Levens
- Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Leonie M Quinn
- Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2600, Australia
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21
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Sanij E, Hannan KM, Xuan J, Yan S, Ahern JE, Trigos AS, Brajanovski N, Son J, Chan KT, Kondrashova O, Lieschke E, Wakefield MJ, Frank D, Ellis S, Cullinane C, Kang J, Poortinga G, Nag P, Deans AJ, Khanna KK, Mileshkin L, McArthur GA, Soong J, Berns EMJJ, Hannan RD, Scott CL, Sheppard KE, Pearson RB. CX-5461 activates the DNA damage response and demonstrates therapeutic efficacy in high-grade serous ovarian cancer. Nat Commun 2020; 11:2641. [PMID: 32457376 PMCID: PMC7251123 DOI: 10.1038/s41467-020-16393-4] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 04/30/2020] [Indexed: 02/06/2023] Open
Abstract
Acquired resistance to PARP inhibitors (PARPi) is a major challenge for the clinical management of high grade serous ovarian cancer (HGSOC). Here, we demonstrate CX-5461, the first-in-class inhibitor of RNA polymerase I transcription of ribosomal RNA genes (rDNA), induces replication stress and activates the DNA damage response. CX-5461 co-operates with PARPi in exacerbating replication stress and enhances therapeutic efficacy against homologous recombination (HR) DNA repair-deficient HGSOC-patient-derived xenograft (PDX) in vivo. We demonstrate CX-5461 has a different sensitivity spectrum to PARPi involving MRE11-dependent degradation of replication forks. Importantly, CX-5461 exhibits in vivo single agent efficacy in a HGSOC-PDX with reduced sensitivity to PARPi by overcoming replication fork protection. Further, we identify CX-5461-sensitivity gene expression signatures in primary and relapsed HGSOC. We propose CX-5461 is a promising therapy in combination with PARPi in HR-deficient HGSOC and also as a single agent for the treatment of relapsed disease.
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Affiliation(s)
- Elaine Sanij
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia.
- Department of Clinical Pathology, University of Melbourne, Parkville, VIC, 3010, Australia.
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Katherine M Hannan
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Acton, 2601, Australia Capital Territory, Australia.
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Jiachen Xuan
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Shunfei Yan
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Jessica E Ahern
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
| | - Anna S Trigos
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Natalie Brajanovski
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
| | - Jinbae Son
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Keefe T Chan
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
| | - Olga Kondrashova
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Elizabeth Lieschke
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
| | - Matthew J Wakefield
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Melbourne Bioinformatics, University of Melbourne, Victoria, 3010, Australia
| | - Daniel Frank
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Sarah Ellis
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Carleen Cullinane
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Jian Kang
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
| | - Gretchen Poortinga
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Medicine, St. Vincent's Hospital, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Purba Nag
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
- School of Environment and Sciences, Griffith University, Nathan, Brisbane, QLD, 4111, Australia
| | - Andrew J Deans
- Department of Medicine, St. Vincent's Hospital, University of Melbourne, Parkville, VIC, 3010, Australia
- Genome Stability Unit, St Vincent's Institute, Fitzroy, VIC, 3065, Australia
| | - Kum Kum Khanna
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Linda Mileshkin
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Grant A McArthur
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Department of Clinical Pathology, University of Melbourne, Parkville, VIC, 3010, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Medicine, St. Vincent's Hospital, University of Melbourne, Parkville, VIC, 3010, Australia
| | - John Soong
- Senhwa Biosciences, Virginia Commonwealth University School of Medicine, San Diego, CA, USA
| | - Els M J J Berns
- Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ross D Hannan
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
- ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Acton, 2601, Australia Capital Territory, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Clare L Scott
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medicine and Health Sciences, Monash University, Clayton, VIC, 3168, Australia
| | - Karen E Sheppard
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Richard B Pearson
- Peter MacCallum Cancer Centre, 305 Grattan St, Melbourne, VIC, 3000, Australia.
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, 3010, Australia.
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia.
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22
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Shohayeb B, Mitchell N, Millard SS, Quinn LM, Ng DCH. Elevated levels of Drosophila Wdr62 promote glial cell growth and proliferation through AURKA signalling to AKT and MYC. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118713. [PMID: 32246948 DOI: 10.1016/j.bbamcr.2020.118713] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/09/2020] [Accepted: 03/30/2020] [Indexed: 12/12/2022]
Abstract
WD40-Repeat Protein 62 (WDR62) is required to maintain neural and glial cell populations during embryonic brain growth. Although elevated expression of WDR62 is frequently associated with several tumour types, potential effects of excess WDR62 on proliferative growth remain undefined. Here, we demonstrate that glia specific overexpression of WDR62 in Drosophila larval brains resulted in increased cell size, over-proliferation and increased brain volume, without overt disruption of tissue organization. We further demonstrate WDR62 promoted over-proliferation and brain overgrowth by activating AURKA and pAKT signalling to increase MYC function in glial cells. Together these data suggest WDR62 normally functions in the glial lineage to activate oncogenic signalling networks, promoting proliferation and brain overgrowth.
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Affiliation(s)
- Belal Shohayeb
- School of Biomedical Science, Faculty of Medicine, University of Queensland, St Lucia, Queensland 4067, Australia
| | - Naomi Mitchell
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Canberra, ACT 260, Australia
| | - S Sean Millard
- School of Biomedical Science, Faculty of Medicine, University of Queensland, St Lucia, Queensland 4067, Australia
| | - Leonie M Quinn
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Canberra, ACT 260, Australia
| | - Dominic C H Ng
- School of Biomedical Science, Faculty of Medicine, University of Queensland, St Lucia, Queensland 4067, Australia.
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23
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CRISPR-based gene knockout screens reveal deubiquitinases involved in HIV-1 latency in two Jurkat cell models. Sci Rep 2020; 10:5350. [PMID: 32210344 PMCID: PMC7093534 DOI: 10.1038/s41598-020-62375-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/10/2020] [Indexed: 12/28/2022] Open
Abstract
The major barrier to a HIV-1 cure is the persistence of latent genomes despite treatment with antiretrovirals. To investigate host factors which promote HIV-1 latency, we conducted a genome-wide functional knockout screen using CRISPR-Cas9 in a HIV-1 latency cell line model. This screen identified IWS1, POLE3, POLR1B, PSMD1, and TGM2 as potential regulators of HIV-1 latency, of which PSMD1 and TMG2 could be confirmed pharmacologically. Further investigation of PSMD1 revealed that an interacting enzyme, the deubiquitinase UCH37, was also involved in HIV-1 latency. We therefore conducted a comprehensive evaluation of the deubiquitinase family by gene knockout, identifying several deubiquitinases, UCH37, USP14, OTULIN, and USP5 as possible HIV-1 latency regulators. A specific inhibitor of USP14, IU1, reversed HIV-1 latency and displayed synergistic effects with other latency reversal agents. IU1 caused degradation of TDP-43, a negative regulator of HIV-1 transcription. Collectively, this study is the first comprehensive evaluation of deubiquitinases in HIV-1 latency and establishes that they may hold a critical role.
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24
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Bisso A, Sabò A, Amati B. MYC in Germinal Center-derived lymphomas: Mechanisms and therapeutic opportunities. Immunol Rev 2019; 288:178-197. [PMID: 30874346 DOI: 10.1111/imr.12734] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 12/11/2018] [Indexed: 12/13/2022]
Abstract
The rearrangement of immunoglobulin loci during the germinal center reaction is associated with an increased risk of chromosomal translocations that activate oncogenes such as MYC, BCL2 or BCL6, thus contributing to the development of B-cell lymphomas. MYC and BCL2 activation are initiating events in Burkitt's (BL) and Follicular Lymphoma (FL), respectively, but can occur at later stages in other subtypes such as Diffuse Large-B Cell Lymphoma (DLBCL). MYC can also be activated during the progression of FL to the transformed stage. Thus, either DLBCL or FL can give rise to aggressive double-hit lymphomas (DHL) with concurrent activation of MYC and BCL2. Research over the last three decades has improved our understanding of the functions of these oncogenes and the basis for their cooperative action in lymphomagenesis. MYC, in particular, is a transcription factor that contributes to cell activation, growth and proliferation, while concomitantly sensitizing cells to apoptosis, the latter being blocked by BCL2. Here, we review our current knowledge about the role of MYC in germinal center B-cells and lymphomas, discuss MYC-induced dependencies that can sensitize cancer cells to select pharmacological inhibitors, and illustrate their therapeutic potential in aggressive lymphomas-and in particular in DHL, in combination with BCL2 inhibitors.
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Affiliation(s)
- Andrea Bisso
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Arianna Sabò
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Bruno Amati
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
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25
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Interaction of the oncoprotein transcription factor MYC with its chromatin cofactor WDR5 is essential for tumor maintenance. Proc Natl Acad Sci U S A 2019; 116:25260-25268. [PMID: 31767764 PMCID: PMC6911241 DOI: 10.1073/pnas.1910391116] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The oncoprotein transcription factor MYC is a validated but challenging anticancer target. In this work, we show that WDR5—a well-structured protein with druggable pockets—could be a focal point for effective anti-MYC therapies. We demonstrate that WDR5 recruits MYC to chromatin to control the expression of genes connected to protein synthesis, a process that is arguably deregulated in all cancers. We also show that disrupting the interaction between MYC and WDR5 causes existing tumors to regress. These findings raise the possibility that the MYC–WDR5 nexus could be targeted to treat cancer. The oncoprotein transcription factor MYC is overexpressed in the majority of cancers. Key to its oncogenic activity is the ability of MYC to regulate gene expression patterns that drive and maintain the malignant state. MYC is also considered a validated anticancer target, but efforts to pharmacologically inhibit MYC have failed. The dependence of MYC on cofactors creates opportunities for therapeutic intervention, but for any cofactor this requires structural understanding of how the cofactor interacts with MYC, knowledge of the role it plays in MYC function, and demonstration that disrupting the cofactor interaction will cause existing cancers to regress. One cofactor for which structural information is available is WDR5, which interacts with MYC to facilitate its recruitment to chromatin. To explore whether disruption of the MYC–WDR5 interaction could potentially become a viable anticancer strategy, we developed a Burkitt's lymphoma system that allows replacement of wild-type MYC for mutants that are defective for WDR5 binding or all known nuclear MYC functions. Using this system, we show that WDR5 recruits MYC to chromatin to control the expression of genes linked to biomass accumulation. We further show that disrupting the MYC–WDR5 interaction within the context of an existing cancer promotes rapid and comprehensive tumor regression in vivo. These observations connect WDR5 to a core tumorigenic function of MYC and establish that, if a therapeutic window can be established, MYC–WDR5 inhibitors could be developed as anticancer agents.
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26
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Scull CE, Schneider DA. Coordinated Control of rRNA Processing by RNA Polymerase I. Trends Genet 2019; 35:724-733. [PMID: 31358304 DOI: 10.1016/j.tig.2019.07.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/25/2019] [Accepted: 07/01/2019] [Indexed: 11/19/2022]
Abstract
Ribosomal RNA (rRNA) is co- and post-transcriptionally processed into active ribosomes. This process is dynamically regulated by direct covalent modifications of the polymerase that synthesizes the rRNA, RNA polymerase I (Pol I), and by interactions with cofactors that influence initiation, elongation, and termination activities of Pol I. The rate of transcription elongation by Pol I directly influences processing of nascent rRNA, and changes in Pol I transcription rate result in alternative rRNA processing events that lead to cellular signaling alterations and stress. It is clear that in divergent species, there exists robust organization of nascent rRNA processing events during transcription elongation. This review evaluates the current state of our understanding of the complex relationship between transcription elongation and rRNA processing.
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Affiliation(s)
- Catherine E Scull
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - David A Schneider
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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27
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The antimalarial drug amodiaquine stabilizes p53 through ribosome biogenesis stress, independently of its autophagy-inhibitory activity. Cell Death Differ 2019; 27:773-789. [PMID: 31285544 PMCID: PMC7205879 DOI: 10.1038/s41418-019-0387-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 06/09/2019] [Accepted: 06/21/2019] [Indexed: 12/11/2022] Open
Abstract
Pharmacological inhibition of ribosome biogenesis is a promising avenue for cancer therapy. Herein, we report a novel activity of the FDA-approved antimalarial drug amodiaquine which inhibits rRNA transcription, a rate-limiting step for ribosome biogenesis, in a dose-dependent manner. Amodiaquine triggers degradation of the catalytic subunit of RNA polymerase I (Pol I), with ensuing RPL5/RPL11-dependent stabilization of p53. Pol I shutdown occurs in the absence of DNA damage and without the subsequent ATM-dependent inhibition of rRNA transcription. RNAseq analysis revealed mechanistic similarities of amodiaquine with BMH-21, the first-in-class Pol I inhibitor, and with chloroquine, the antimalarial analog of amodiaquine, with well-established autophagy-inhibitory activity. Interestingly, autophagy inhibition caused by amodiaquine is not involved in the inhibition of rRNA transcription, suggesting two independent anticancer mechanisms. In vitro, amodiaquine is more efficient than chloroquine in restraining the proliferation of human cell lines derived from colorectal carcinomas, a cancer type with predicted susceptibility to ribosome biogenesis stress. Taken together, our data reveal an unsuspected activity of a drug approved and used in the clinics for over 30 years, and provide rationale for repurposing amodiaquine in cancer therapy.
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28
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Khot A, Brajanovski N, Cameron DP, Hein N, Maclachlan KH, Sanij E, Lim J, Soong J, Link E, Blombery P, Thompson ER, Fellowes A, Sheppard KE, McArthur GA, Pearson RB, Hannan RD, Poortinga G, Harrison SJ. First-in-Human RNA Polymerase I Transcription Inhibitor CX-5461 in Patients with Advanced Hematologic Cancers: Results of a Phase I Dose-Escalation Study. Cancer Discov 2019; 9:1036-1049. [PMID: 31092402 DOI: 10.1158/2159-8290.cd-18-1455] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 04/11/2019] [Accepted: 05/10/2019] [Indexed: 11/16/2022]
Abstract
RNA polymerase I (Pol I) transcription of ribosomal RNA genes (rDNA) is tightly regulated downstream of oncogenic pathways, and its dysregulation is a common feature in cancer. We evaluated CX-5461, the first-in-class selective rDNA transcription inhibitor, in a first-in-human, phase I dose-escalation study in advanced hematologic cancers. Administration of CX-5461 intravenously once every 3 weeks to 5 cohorts determined an MTD of 170 mg/m2, with a predictable pharmacokinetic profile. The dose-limiting toxicity was palmar-plantar erythrodysesthesia; photosensitivity was a dose-independent adverse event (AE), manageable by preventive measures. CX-5461 induced rapid on-target inhibition of rDNA transcription, with p53 activation detected in tumor cells from one patient achieving a clinical response. One patient with anaplastic large cell lymphoma attained a prolonged partial response and 5 patients with myeloma and diffuse large B-cell lymphoma achieved stable disease as best response. CX-5461 is safe at doses associated with clinical benefit and dermatologic AEs are manageable. SIGNIFICANCE: CX-5461 is a first-in-class selective inhibitor of rDNA transcription. This first-in-human study establishes the feasibility of targeting this process, demonstrating single-agent antitumor activity against advanced hematologic cancers with predictable pharmacokinetics and a safety profile allowing prolonged dosing. Consistent with preclinical data, antitumor activity was observed in TP53 wild-type and mutant malignancies.This article is highlighted in the In This Issue feature, p. 983.
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Affiliation(s)
- Amit Khot
- Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Victoria, Australia
| | - Natalie Brajanovski
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Donald P Cameron
- The ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Australian Capital Territory, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - Nadine Hein
- The ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Australian Capital Territory, Australia
| | - Kylee H Maclachlan
- Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Victoria, Australia.,Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - Elaine Sanij
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Pathology, University of Melbourne, Parkville, Victoria, Australia
| | - John Lim
- Senhwa Biosciences, Inc., New Taipei City, Taiwan, Republic of China
| | - John Soong
- Senhwa Biosciences, Inc., New Taipei City, Taiwan, Republic of China
| | - Emma Link
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Piers Blombery
- Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Ella R Thompson
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Andrew Fellowes
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Karen E Sheppard
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Grant A McArthur
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Richard B Pearson
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ross D Hannan
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,The ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, Australian National University, Australian Capital Territory, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Gretchen Poortinga
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia. .,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Medicine, St. Vincent's Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Simon J Harrison
- Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Victoria, Australia. .,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
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29
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Diesch J, Bywater MJ, Sanij E, Cameron DP, Schierding W, Brajanovski N, Son J, Sornkom J, Hein N, Evers M, Pearson RB, McArthur GA, Ganley ARD, O’Sullivan JM, Hannan RD, Poortinga G. Changes in long-range rDNA-genomic interactions associate with altered RNA polymerase II gene programs during malignant transformation. Commun Biol 2019; 2:39. [PMID: 30701204 PMCID: PMC6349880 DOI: 10.1038/s42003-019-0284-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 12/28/2018] [Indexed: 12/15/2022] Open
Abstract
The three-dimensional organization of the genome contributes to its maintenance and regulation. While chromosomal regions associate with nucleolar ribosomal RNA genes (rDNA), the biological significance of rDNA-genome interactions and whether they are dynamically regulated during disease remain unclear. rDNA chromatin exists in multiple inactive and active states and their transition is regulated by the RNA polymerase I transcription factor UBTF. Here, using a MYC-driven lymphoma model, we demonstrate that during malignant progression the rDNA chromatin converts to the open state, which is required for tumor cell survival. Moreover, this rDNA transition co-occurs with a reorganization of rDNA-genome contacts which correlate with gene expression changes at associated loci, impacting gene ontologies including B-cell differentiation, cell growth and metabolism. We propose that UBTF-mediated conversion to open rDNA chromatin during malignant transformation contributes to the regulation of specific gene pathways that regulate growth and differentiation through reformed long-range physical interactions with the rDNA.
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Affiliation(s)
- Jeannine Diesch
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Present Address: Josep Carreras Leukaemia Research Institute, Barcelona, 08021 Spain
| | - Megan J. Bywater
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Present Address: QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029 Australia
| | - Elaine Sanij
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Department of Pathology, University of Melbourne, Parkville, VIC 3010 Australia
| | - Donald P. Cameron
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
| | - William Schierding
- Liggins Institute, The University of Auckland, Auckland, 1023 New Zealand
| | - Natalie Brajanovski
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
| | - Jinbae Son
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
| | - Jirawas Sornkom
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
| | - Nadine Hein
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601 Australia
| | - Maurits Evers
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601 Australia
| | - Richard B. Pearson
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, 3800 VIC Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC 3010 Australia
| | - Grant A. McArthur
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC 3065 Australia
| | - Austen R. D. Ganley
- School of Biological Sciences, The University of Auckland, Auckland, 1010 New Zealand
| | | | - Ross D. Hannan
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, Australian National University, Canberra, ACT 2601 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, 3800 VIC Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC 3010 Australia
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD 4072 Australia
| | - Gretchen Poortinga
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC 3000 Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC 3010 Australia
- Department of Medicine, St Vincent’s Hospital, University of Melbourne, Fitzroy, VIC 3065 Australia
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Warmerdam DO, Wolthuis RMF. Keeping ribosomal DNA intact: a repeating challenge. Chromosome Res 2018; 27:57-72. [PMID: 30556094 PMCID: PMC6394564 DOI: 10.1007/s10577-018-9594-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 11/20/2018] [Accepted: 11/29/2018] [Indexed: 02/06/2023]
Abstract
More than half of the human genome consists of repetitive sequences, with the ribosomal DNA (rDNA) representing two of the largest repeats. Repetitive rDNA sequences may form a threat to genomic integrity and cellular homeostasis due to the challenging aspects of their transcription, replication, and repair. Predisposition to cancer, premature aging, and neurological impairment in ataxia-telangiectasia and Bloom syndrome, for instance, coincide with increased cellular rDNA repeat instability. However, the mechanisms by which rDNA instability contributes to these hereditary syndromes and tumorigenesis remain unknown. Here, we review how cells govern rDNA stability and how rDNA break repair influences expansion and contraction of repeat length, a process likely associated with human disease. Recent advancements in CRISPR-based genome engineering may help to explain how cells keep their rDNA intact in the near future.
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Affiliation(s)
- Daniël O Warmerdam
- CRISPR Platform, University of Amsterdam, Cancer Center Amsterdam, Amsterdam UMC, Meibergdreef 9, 1105 AZ, Amsterdam, the Netherlands.
| | - Rob M F Wolthuis
- Section of Oncogenetics, Department of Clinical Genetics, Vrije Universiteit Amsterdam, Cancer Center Amsterdam, Amsterdam UMC, de Boelelaan 1117, 1081 HV, Amsterdam, the Netherlands
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31
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Agrawal S, Ganley ARD. The conservation landscape of the human ribosomal RNA gene repeats. PLoS One 2018; 13:e0207531. [PMID: 30517151 PMCID: PMC6281188 DOI: 10.1371/journal.pone.0207531] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 11/01/2018] [Indexed: 01/27/2023] Open
Abstract
Ribosomal RNA gene repeats (rDNA) encode ribosomal RNA, a major component of ribosomes. Ribosome biogenesis is central to cellular metabolic regulation, and several diseases are associated with rDNA dysfunction, notably cancer, However, its highly repetitive nature has severely limited characterization of the elements responsible for rDNA function. Here we make use of phylogenetic footprinting to provide a comprehensive list of novel, potentially functional elements in the human rDNA. Complete rDNA sequences for six non-human primate species were constructed using de novo whole genome assemblies. These new sequences were used to determine the conservation profile of the human rDNA, revealing 49 conserved regions in the rDNA intergenic spacer (IGS). To provide insights into the potential roles of these conserved regions, the conservation profile was integrated with functional genomics datasets. We find two major zones that contain conserved elements characterised by enrichment of transcription-associated chromatin factors, and transcription. Conservation of some IGS transcripts in the apes underpins the potential functional significance of these transcripts and the elements controlling their expression. Our results characterize the conservation landscape of the human IGS and suggest that noncoding transcription and chromatin elements are conserved and important features of this unique genomic region.
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Affiliation(s)
- Saumya Agrawal
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand
| | - Austen R. D. Ganley
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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32
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Abstract
The genetic concept of synthetic lethality has now been validated clinically through the demonstrated efficacy of poly(ADP-ribose) polymerase (PARP) inhibitors for the treatment of cancers in individuals with germline loss-of-function mutations in either BRCA1 or BRCA2. Three different PARP inhibitors have now been approved for the treatment of patients with BRCA-mutant ovarian cancer and one for those with BRCA-mutant breast cancer; these agents have also shown promising results in patients with BRCA-mutant prostate cancer. Here, we describe a number of other synthetic lethal interactions that have been discovered in cancer. We discuss some of the underlying principles that might increase the likelihood of clinical efficacy and how new computational and experimental approaches are now facilitating the discovery and validation of synthetic lethal interactions. Finally, we make suggestions on possible future directions and challenges facing researchers in this field.
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Affiliation(s)
- Alan Ashworth
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA.
| | - Christopher J Lord
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK.
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33
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Lawrence MG, Obinata D, Sandhu S, Selth LA, Wong SQ, Porter LH, Lister N, Pook D, Pezaro CJ, Goode DL, Rebello RJ, Clark AK, Papargiris M, Van Gramberg J, Hanson AR, Banks P, Wang H, Niranjan B, Keerthikumar S, Hedwards S, Huglo A, Yang R, Henzler C, Li Y, Lopez-Campos F, Castro E, Toivanen R, Azad A, Bolton D, Goad J, Grummet J, Harewood L, Kourambas J, Lawrentschuk N, Moon D, Murphy DG, Sengupta S, Snow R, Thorne H, Mitchell C, Pedersen J, Clouston D, Norden S, Ryan A, Dehm SM, Tilley WD, Pearson RB, Hannan RD, Frydenberg M, Furic L, Taylor RA, Risbridger GP. Patient-derived Models of Abiraterone- and Enzalutamide-resistant Prostate Cancer Reveal Sensitivity to Ribosome-directed Therapy. Eur Urol 2018; 74:562-572. [PMID: 30049486 DOI: 10.1016/j.eururo.2018.06.020] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/13/2018] [Indexed: 01/16/2023]
Abstract
BACKGROUND The intractability of castration-resistant prostate cancer (CRPC) is exacerbated by tumour heterogeneity, including diverse alterations to the androgen receptor (AR) axis and AR-independent phenotypes. The availability of additional models encompassing this heterogeneity would facilitate the identification of more effective therapies for CRPC. OBJECTIVE To discover therapeutic strategies by exploiting patient-derived models that exemplify the heterogeneity of CRPC. DESIGN, SETTING, AND PARTICIPANTS Four new patient-derived xenografts (PDXs) were established from independent metastases of two patients and characterised using integrative genomics. A panel of rationally selected drugs was tested using an innovative ex vivo PDX culture system. INTERVENTION The following drugs were evaluated: AR signalling inhibitors (enzalutamide and galeterone), a PARP inhibitor (talazoparib), a chemotherapeutic (cisplatin), a CDK4/6 inhibitor (ribociclib), bromodomain and extraterminal (BET) protein inhibitors (iBET151 and JQ1), and inhibitors of ribosome biogenesis/function (RNA polymerase I inhibitor CX-5461 and pan-PIM kinase inhibitor CX-6258). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Drug efficacy in ex vivo cultures of PDX tissues was evaluated using immunohistochemistry for Ki67 and cleaved caspase-3 levels. Candidate drugs were also tested for antitumour efficacy in vivo, with tumour volume being the primary endpoint. Two-tailed t tests were used to compare drug and control treatments. RESULTS AND LIMITATIONS Integrative genomics revealed that the new PDXs exhibited heterogeneous mechanisms of resistance, including known and novel AR mutations, genomic structural rearrangements of the AR gene, and a neuroendocrine-like AR-null phenotype. Despite their heterogeneity, all models were sensitive to the combination of ribosome-targeting agents CX-5461 and CX-6258. CONCLUSIONS This study demonstrates that ribosome-targeting drugs may be effective against diverse CRPC subtypes including AR-null disease, and highlights the potential of contemporary patient-derived models to prioritise treatment strategies for clinical translation. PATIENT SUMMARY Diverse types of therapy-resistant prostate cancers are sensitive to a new combination of drugs that inhibit protein synthesis pathways in cancer cells.
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Affiliation(s)
- Mitchell G Lawrence
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Melbourne Urological Research Alliance (MURAL), Melbourne, VIC, Australia
| | - Daisuke Obinata
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - Shahneen Sandhu
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Division of Cancer Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Cancer Tissue Collection After Death (CASCADE) Program, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Luke A Selth
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Men's Health, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Stephen Q Wong
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Molecular Biomarkers and Translational Genomics Lab, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Laura H Porter
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - Natalie Lister
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - David Pook
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Medical Oncology, Monash Health, Clayton, VIC, Australia
| | - Carmel J Pezaro
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Eastern Health and Monash University Eastern Health Clinical School, Box Hill, VIC, Australia
| | - David L Goode
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Computational Cancer Biology Program, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Richard J Rebello
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Ashlee K Clark
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - Melissa Papargiris
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Melbourne Urological Research Alliance (MURAL), Melbourne, VIC, Australia; Australian Prostate Cancer Bioresource, VIC Node, Monash University, Clayton, VIC, Australia
| | - Jenna Van Gramberg
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Australian Prostate Cancer Bioresource, VIC Node, Monash University, Clayton, VIC, Australia
| | - Adrienne R Hanson
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Men's Health, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Patricia Banks
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Hong Wang
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - Birunthi Niranjan
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
| | - Shivakumar Keerthikumar
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Computational Cancer Biology Program, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Shelley Hedwards
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Alisee Huglo
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Rendong Yang
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN, USA
| | - Christine Henzler
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN, USA
| | - Yingming Li
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | | | - Elena Castro
- Spanish National Cancer Research Centre, Madrid, Spain
| | - Roxanne Toivanen
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Arun Azad
- Medical Oncology, Monash Health, Clayton, VIC, Australia; Department of Medicine, School of Clinical Sciences, Monash University, Clayton, VIC, Australia
| | - Damien Bolton
- Department of Urology, Austin Hospital, The University of Melbourne, Melbourne Heidelberg, VIC, Australia; Department of Surgery, The University of Melbourne, Parkville, VIC, Australia
| | - Jeremy Goad
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Division of Cancer Surgery, Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia
| | - Jeremy Grummet
- Epworth Healthcare, Melbourne, VIC, Australia; Department of Surgery, Central Clinical School, Monash University, Clayton, VIC, Australia; Australian Urology Associates, Melbourne, VIC, Australia
| | - Laurence Harewood
- Department of Surgery, The University of Melbourne, Parkville, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia
| | - John Kourambas
- Department of Medicine, Monash Health, Casey Hospital, Berwick, VIC, Australia
| | - Nathan Lawrentschuk
- Division of Cancer Surgery, Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, VIC, Australia; Department of Surgery, Austin Health, The University of Melbourne, Heidelberg, VIC, Australia
| | - Daniel Moon
- Division of Cancer Surgery, Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia; Australian Urology Associates, Melbourne, VIC, Australia; Central Clinical School, Monash University, Clayton, VIC, Australia; The Epworth Prostate Centre, Epworth Hospital, Richmond, VIC, Australia
| | - Declan G Murphy
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Division of Cancer Surgery, Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia
| | - Shomik Sengupta
- Eastern Health and Monash University Eastern Health Clinical School, Box Hill, VIC, Australia; Department of Urology, Austin Hospital, The University of Melbourne, Melbourne Heidelberg, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia; Department of Surgery, Austin Health, The University of Melbourne, Heidelberg, VIC, Australia; Epworth Freemasons, Epworth Health, East Melbourne, VIC, Australia
| | - Ross Snow
- Australian Urology Associates, Melbourne, VIC, Australia
| | - Heather Thorne
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; kConFab, Research Department, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Catherine Mitchell
- Department of Pathology, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - John Pedersen
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; TissuPath, Mount Waverley, VIC, Australia
| | | | - Sam Norden
- TissuPath, Mount Waverley, VIC, Australia
| | | | - Scott M Dehm
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA; Departments of Laboratory Medicine and Pathology and Urology, University of Minnesota, Minneapolis, MN, USA
| | - Wayne D Tilley
- Dame Roma Mitchell Cancer Research Laboratories and Freemasons Foundation Centre for Men's Health, Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Richard B Pearson
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia; Oncogenic Signaling and Growth Control Program, Cancer Research Division, Peter MacCallum Cancer Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Ross D Hannan
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, VIC, Australia; Oncogenic Signaling and Growth Control Program, Cancer Research Division, Peter MacCallum Cancer Centre, University of Melbourne, Melbourne, VIC, Australia; ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, Australian National University, ACT, Australia
| | - Mark Frydenberg
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Epworth Healthcare, Melbourne, VIC, Australia; Australian Urology Associates, Melbourne, VIC, Australia; Department of Surgery, Monash University, Clayton, VIC, Australia
| | - Luc Furic
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia
| | - Renea A Taylor
- Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Melbourne Urological Research Alliance (MURAL), Melbourne, VIC, Australia; Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Physiology, Monash University, Clayton, VIC, Australia
| | - Gail P Risbridger
- Monash Partners Comprehensive Cancer Consortium, Monash Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia; Cancer Research Division, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Melbourne Urological Research Alliance (MURAL), Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, Australia.
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Núñez Villacís L, Wong MS, Ferguson LL, Hein N, George AJ, Hannan KM. New Roles for the Nucleolus in Health and Disease. Bioessays 2018; 40:e1700233. [PMID: 29603296 DOI: 10.1002/bies.201700233] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/02/2018] [Indexed: 12/31/2022]
Abstract
Over the last decade, our appreciation of the importance of the nucleolus for cellular function has progressed from the ordinary to the extraordinary. We no longer think of the nucleolus as simply the site of ribosome production, or a dynamic subnuclear body noted by pathologists for its changes in size and shape with malignancy. Instead, the nucleolus has emerged as a key controller of many cellular processes that are fundamental to normal cell homeostasis and the target for dysregulation in many human diseases; in some cases, independent of its functions in ribosome biogenesis. These extra-nucleolar or new functions, which we term "non-canonical" to distinguish them from the more traditional role of the nucleolus in ribosome synthesis, are the focus of this review. In particular, we explore how these non-canonical functions may provide novel insights into human disease and in some cases new targets for therapeutic development.
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Affiliation(s)
- Lorena Núñez Villacís
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia
| | - Mei S Wong
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia.,Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Center, Melbourne, 3000, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, 3010, Australia
| | - Laura L Ferguson
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia
| | - Nadine Hein
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia
| | - Amee J George
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia.,School of Biomedical Sciences, University of Queensland, St Lucia, 4067, Australia.,Department of Clinical Pathology, The University of Melbourne, Parkville, 3010, Australia
| | - Katherine M Hannan
- ACRF Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Acton, 2601, Australia.,Department of Biochemistry, The University of Melbourne, Parkville, 3010, Australia
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35
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Chang CYY, Lai MT, Chen Y, Yang CW, Chang HW, Lu CC, Chen CM, Chan C, Chung C, Tseng CC, Hwang T, Sheu JJC, Tsai FJ. Up-regulation of ribosome biogenesis by MIR196A2 genetic variation promotes endometriosis development and progression. Oncotarget 2018; 7:76713-76725. [PMID: 27741504 PMCID: PMC5363543 DOI: 10.18632/oncotarget.11536] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 08/09/2016] [Indexed: 12/28/2022] Open
Abstract
Aberrant miRNA expression has been reported in endometriosis and miRNA gene polymorphisms have been linked to cancer. Because certain ovarian cancers arise from endometriosis, we genotyped seven cancer-related miRNA single nucleotide polymorphisms (MiRSNPs) to investigate their possible roles in endometriosis. Genetic variants in MIR196A2 (rs11614913) and MIR100 (rs1834306) were found to be associated with endometriosis development and related clinical phenotypes, such as infertility and pain. Downstream analysis of the MIR196A2 risk allele revealed upregulation of rRNA editing and protein synthesis genes, suggesting hyper-activation of ribosome biogenesis as a driving force for endometriosis progression. Clinical studies confirmed higher levels of small nucleolar RNAs and ribosomal proteins in atypical endometriosis lesions, and this was more pronounced in the associated ovarian clear cell carcinomas. Treating ovarian clear cells with CX5461, an RNA polymerase I inhibitor, suppressed cell growth and mobility followed by cell cycle arrest at G2/M stage and apoptosis. Our study thus uncovered a novel tumorigenesis pathway triggered by the cancer-related MIR196A2 risk allele during endometriosis development and progression. We suggest that anti-RNA polymerase I therapy may be efficacious for treating endometriosis and associated malignancies.
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Affiliation(s)
- Cherry Yin-Yi Chang
- Department of Obstetrics and Gynecology, China Medical University Hospital, Taichung, Taiwan.,Institute of Environmental Health, China Medical University, Taichung, Taiwan
| | - Ming-Tsung Lai
- Department of Pathology, Taichung Hospital, Ministry of Health and Welfare, Taichung, Taiwan
| | - Yi Chen
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan
| | - Ching-Wen Yang
- The Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan.,Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Hui-Wen Chang
- School of Medicine, China Medical University, Taichung, Taiwan
| | - Cheng-Chan Lu
- The Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chih-Mei Chen
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan
| | - Carmen Chan
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan
| | - Ching Chung
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan
| | - Chun-Cheng Tseng
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Tritium Hwang
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Jim Jinn-Chyuan Sheu
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan.,Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan.,School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Fuu-Jen Tsai
- Human Genetic Center, China Medical University Hospital, Taichung, Taiwan.,School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
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36
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Quin J, Chan KT, Devlin JR, Cameron DP, Diesch J, Cullinane C, Ahern J, Khot A, Hein N, George AJ, Hannan KM, Poortinga G, Sheppard KE, Khanna KK, Johnstone RW, Drygin D, McArthur GA, Pearson RB, Sanij E, Hannan RD. Inhibition of RNA polymerase I transcription initiation by CX-5461 activates non-canonical ATM/ATR signaling. Oncotarget 2018; 7:49800-49818. [PMID: 27391441 PMCID: PMC5226549 DOI: 10.18632/oncotarget.10452] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/13/2016] [Indexed: 02/07/2023] Open
Abstract
RNA polymerase I (Pol I)-mediated transcription of the ribosomal RNA genes (rDNA) is confined to the nucleolus and is a rate-limiting step for cell growth and proliferation. Inhibition of Pol I by CX-5461 can selectively induce p53-mediated apoptosis of tumour cells in vivo. Currently, CX-5461 is in clinical trial for patients with advanced haematological malignancies (Peter Mac, Melbourne). Here we demonstrate that CX-5461 also induces p53-independent cell cycle checkpoints mediated by ATM/ATR signaling in the absence of DNA damage. Further, our data demonstrate that the combination of drugs targeting ATM/ATR signaling and CX-5461 leads to enhanced therapeutic benefit in treating p53-null tumours in vivo, which are normally refractory to each drug alone. Mechanistically, we show that CX-5461 induces an unusual chromatin structure in which transcriptionally competent relaxed rDNA repeats are devoid of transcribing Pol I leading to activation of ATM signaling within the nucleoli. Thus, we propose that acute inhibition of Pol transcription initiation by CX-5461 induces a novel nucleolar stress response that can be targeted to improve therapeutic efficacy.
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Affiliation(s)
- Jaclyn Quin
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Keefe T Chan
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia
| | - Jennifer R Devlin
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Institute for Molecular Medicine Finland, Biomedicum 2, Helsinki, Finland
| | - Donald P Cameron
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - Jeannine Diesch
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Josep Carreras Institute for Leukaemia Research (IJC), Campus ICO-HGTP, Badalona, Barcelona, Spain
| | - Carleen Cullinane
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia
| | - Jessica Ahern
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia
| | - Amit Khot
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia
| | - Nadine Hein
- The John Curtin School of Medical Research, Australian National University, Acton, ACT, Australia
| | - Amee J George
- The John Curtin School of Medical Research, Australian National University, Acton, ACT, Australia.,Department of Pathology, University of Melbourne, Parkville, Victoria, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Katherine M Hannan
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,The John Curtin School of Medical Research, Australian National University, Acton, ACT, Australia
| | - Gretchen Poortinga
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia
| | - Karen E Sheppard
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - Kum Kum Khanna
- QIMR Berghofer Medical Research Institute, Brisbane City, Qld, Australia
| | - Ricky W Johnstone
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Pathology, University of Melbourne, Parkville, Victoria, Australia
| | | | - Grant A McArthur
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Pathology, University of Melbourne, Parkville, Victoria, Australia.,Department of Medicine, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia
| | - Richard B Pearson
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Elaine Sanij
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Pathology, University of Melbourne, Parkville, Victoria, Australia
| | - Ross D Hannan
- Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,The John Curtin School of Medical Research, Australian National University, Acton, ACT, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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37
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Kang J, Kusnadi EP, Ogden AJ, Hicks RJ, Bammert L, Kutay U, Hung S, Sanij E, Hannan RD, Hannan KM, Pearson RB. Amino acid-dependent signaling via S6K1 and MYC is essential for regulation of rDNA transcription. Oncotarget 2018; 7:48887-48904. [PMID: 27385002 PMCID: PMC5226478 DOI: 10.18632/oncotarget.10346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 06/15/2016] [Indexed: 12/25/2022] Open
Abstract
Dysregulation of RNA polymerase I (Pol I)-dependent ribosomal DNA (rDNA) transcription is a consistent feature of malignant transformation that can be targeted to treat cancer. Understanding how rDNA transcription is coupled to the availability of growth factors and nutrients will provide insight into how ribosome biogenesis is maintained in a tumour environment characterised by limiting nutrients. We demonstrate that modulation of rDNA transcription initiation, elongation and rRNA processing is an immediate, co-regulated response to altered amino acid abundance, dependent on both mTORC1 activation of S6K1 and MYC activity. Growth factors regulate rDNA transcription initiation while amino acids modulate growth factor-dependent rDNA transcription by primarily regulating S6K1-dependent rDNA transcription elongation and processing. Thus, we show for the first time amino acids regulate rRNA synthesis by a distinct, post-initiation mechanism, providing a novel model for integrated control of ribosome biogenesis that has implications for understanding how this process is dysregulated in cancer.
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Affiliation(s)
- Jian Kang
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Eric P Kusnadi
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Allison J Ogden
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Rodney J Hicks
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Molecular Imaging and Targeted Therapeutics Laboratory, Cancer Therapeutics Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
| | - Lukas Bammert
- Institute of Biochemistry, Department of Biology, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland
| | - Ulrike Kutay
- Institute of Biochemistry, Department of Biology, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland
| | - Sandy Hung
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital & Department of Ophthalmology, University of Melbourne, East Melbourne, Victoria, Australia
| | - Elaine Sanij
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Ross D Hannan
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia.,Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberaa, ACT, Australia
| | - Katherine M Hannan
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberaa, ACT, Australia
| | - Richard B Pearson
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
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38
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Lafita-Navarro MDC, Blanco R, Mata-Garrido J, Liaño-Pons J, Tapia O, García-Gutiérrez L, García-Alegría E, Berciano MT, Lafarga M, León J. MXD1 localizes in the nucleolus, binds UBF and impairs rRNA synthesis. Oncotarget 2018; 7:69536-69548. [PMID: 27588501 PMCID: PMC5342496 DOI: 10.18632/oncotarget.11766] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/26/2016] [Indexed: 12/16/2022] Open
Abstract
MXD1 is a protein that interacts with MAX, to form a repressive transcription factor. MXD1-MAX binds E-boxes. MXD1-MAX antagonizes the transcriptional activity of the MYC oncoprotein in most models. It has been reported that MYC overexpression leads to augmented RNA synthesis and ribosome biogenesis, which is a relevant activity in MYC-mediated tumorigenesis. Here we describe that MXD1, but not MYC or MNT, localizes to the nucleolus in a wide array of cell lines derived from different tissues (carcinoma, leukemia) as well as in embryonic stem cells. MXD1 also localizes in the nucleolus of primary tissue cells as neurons and Sertoli cells. The nucleolar localization of MXD1 was confirmed by co-localization with UBF. Co-immunoprecipitation experiments showed that MXD1 interacted with UBF and proximity ligase assays revealed that this interaction takes place in the nucleolus. Furthermore, chromatin immunoprecipitation assays showed that MXD1 was bound in the transcribed rDNA chromatin, where it co-localizes with UBF, but also in the ribosomal intergenic regions. The MXD1 involvement in rRNA synthesis was also suggested by the nucleolar segregation upon rRNA synthesis inhibition by actinomycin D. Silencing of MXD1 with siRNAs resulted in increased synthesis of pre-rRNA while enforced MXD1 expression reduces it. The results suggest a new role for MXD1, which is the control of ribosome biogenesis. This new MXD1 function would be important to curb MYC activity in tumor cells.
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Affiliation(s)
- Maria Del Carmen Lafita-Navarro
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain.,Present address: Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Rosa Blanco
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain
| | - Jorge Mata-Garrido
- Department of Anatomy and Cell Biology and Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), University of Cantabria-IDIVAL, Santander, Spain
| | - Judit Liaño-Pons
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain
| | - Olga Tapia
- Department of Anatomy and Cell Biology and Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), University of Cantabria-IDIVAL, Santander, Spain
| | - Lucía García-Gutiérrez
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain
| | - Eva García-Alegría
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain.,Present address: Stem Cell Hematopoiesis Group, Cancer Research UK Manchester Institute, University of Manchester, Manchester, United Kingdom
| | - María T Berciano
- Department of Anatomy and Cell Biology and Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), University of Cantabria-IDIVAL, Santander, Spain
| | - Miguel Lafarga
- Department of Anatomy and Cell Biology and Centro de Investigación en Red sobre Enfermedades Neurodegenerativas (CIBERNED), University of Cantabria-IDIVAL, Santander, Spain
| | - Javier León
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, and Department of Molecular Biology, University of Cantabria, Santander, Spain
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39
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Undermining ribosomal RNA transcription in both the nucleolus and mitochondrion: an offbeat approach to target MYC-driven cancer. Oncotarget 2018; 9:5016-5031. [PMID: 29435159 PMCID: PMC5797030 DOI: 10.18632/oncotarget.23579] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 12/09/2017] [Indexed: 01/09/2023] Open
Abstract
The MYC transcription factor coordinates, via different RNA polymerases, the transcription of both ribosomal RNA (rRNA) and protein genes necessary for nucleolar as well as mitochondrial ribogenesis. In this study we tested if MYC-coordination of rRNA transcription in the nucleolus and in the mitochondrion drives (cancer) cell proliferation. Here we show that the anti-proliferative effect of CX-5461, a Pol I inhibitor of rRNA transcription, in ovarian (cancer) cell contexts characterized by MYC overexpression is enhanced either by 2'-C-Methyl Adenosine (2'-C-MeA), a ribonucleoside that inhibits POLRMT mitochondrial rRNA (mt-rRNA) transcription and doxycycline, a tetracycline known to affect mitochondrial translation. Thus, hindering not only mt-rRNA transcription, but also mitoribosome function in MYC-overexpressing ovarian (cancer) cells, potentiates the antiproliferative effect of CX-5461. Targeting MYC-regulated rRNA transcription and ribogenesis in both the nucleolus and mitochondrion seems to be a novel approach worth of consideration for treating MYC-driven cancer.
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40
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MYC-family protein overexpression and prominent nucleolar formation represent prognostic indicators and potential therapeutic targets for aggressive high-MKI neuroblastomas: a report from the children's oncology group. Oncotarget 2017; 9:6416-6432. [PMID: 29464082 PMCID: PMC5814222 DOI: 10.18632/oncotarget.23740] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/13/2017] [Indexed: 12/29/2022] Open
Abstract
Neuroblastomas with a high mitosis-karyorrhexis index (High-MKI) are often associated with MYCN amplification, MYCN protein overexpression and adverse clinical outcome. However, the prognostic effect of MYC-family protein expression on these neuroblastomas is less understood, especially when MYCN is not amplified. To address this, MYCN and MYC protein expression in High-MKI cases (120 MYCN amplified and 121 non-MYCN amplified) was examined by immunohistochemistry. The majority (101) of MYCN-amplified High-MKI tumors were MYCN(+), leaving one MYC(+), 2 both(+), and 16 both(−)/(+/−), whereas non-MYCN-amplified cases appeared heterogeneous, including 7 MYCN(+), 36 MYC(+), 3 both(+), and 75 both(−)/(+/−) tumors. These MYC-family proteins(+), or MYC-family driven tumors, were most likely to have prominent nucleolar (PN) formation (indicative of augmented rRNA synthesis). High-MKI neuroblastoma patients showed a poor survival irrespective of MYCN amplification. However, patients with MYC-family driven High-MKI neuroblastomas had significantly lower survival than those with non-MYC-family driven tumors. MYCN(+), MYC-family protein(+), PN(+), and clinical stage independently predicted poor survival. Specific inhibition of hyperactive rRNA synthesis and protein translation was shown to be an effective way to suppress MYC/MYCN protein expression and neuroblastoma growth. Together, MYC-family protein overexpression and PN formation should be included in new neuroblastoma risk stratification and considered for potential therapeutic targets.
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41
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Emerging Therapeutics to Overcome Chemoresistance in Epithelial Ovarian Cancer: A Mini-Review. Int J Mol Sci 2017; 18:ijms18102171. [PMID: 29057791 PMCID: PMC5666852 DOI: 10.3390/ijms18102171] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/13/2017] [Accepted: 10/16/2017] [Indexed: 12/14/2022] Open
Abstract
Ovarian cancer is the fifth leading cause of cancer death among women and the most lethal gynecologic malignancy. One of the leading causes of death in high-grade serous ovarian cancer (HGSOC) is chemoresistant disease, which may present as intrinsic or acquired resistance to therapies. Here we discuss some of the known molecular mechanisms of chemoresistance that have been exhaustively investigated in chemoresistant ovarian cancer, including drug efflux pump multidrug resistance protein 1 (MDR1), the epithelial–mesenchymal transition, DNA damage and repair capacity. We also discuss novel therapeutics that may address some of the challenges in bringing approaches that target chemoresistant processes from bench to bedside. Some of these new therapies include novel drug delivery systems, targets that may halt adaptive changes in the tumor, exploitation of tumor mutations that leave cancer cells vulnerable to irreversible damage, and novel drugs that target ribosomal biogenesis, a process that may be uniquely different in cancer versus non-cancerous cells. Each of these approaches, or a combination of them, may provide a greater number of positive outcomes for a broader population of HGSOC patients.
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42
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Madru C, Leulliot N, Lebaron S. [Ribosomes synthesis at the heart of cell proliferation]. Med Sci (Paris) 2017; 33:613-619. [PMID: 28990563 DOI: 10.1051/medsci/20173306018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Ribosomes are central to gene expression. Their assembly is a complex and an energy consuming process. Many controls exist to make it possible a fine-tuning of ribosome production adapted to cell needs. In this review, we describe recent advances in the characterisation of the links occurring between ribosome synthesis and cell proliferation control. Defects in ribosome biogenesis directly impede cellular cycle and slow-down proliferation. Among the different factors involved, we could define the 5S particle, a ribosome sub-complex, as a key-regulator of p53 and other tumour suppressors such as pRB. This cross-talk between ribosome neogenesis defects and proliferation and cellular cycle also involves other cell cycle controls such as p14ARF, SRSF1 or PRAS40 pathways. These data place ribosome synthesis at the heart of cell proliferation and offer new therapeutic strategies against cancer.
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Affiliation(s)
- Clément Madru
- Laboratoire de Cristallographie et RMN Biologiques, UMR, CNRS 8015, Université Paris Descartes, Faculté de Pharmacie, Sorbonne Paris Cité, 75006 Paris, France
| | - Nicolas Leulliot
- Laboratoire de Cristallographie et RMN Biologiques, UMR, CNRS 8015, Université Paris Descartes, Faculté de Pharmacie, Sorbonne Paris Cité, 75006 Paris, France
| | - Simon Lebaron
- Laboratoire de Cristallographie et RMN Biologiques, UMR, CNRS 8015, Université Paris Descartes, Faculté de Pharmacie, Sorbonne Paris Cité, 75006 Paris, France - Institut national de la santé et de la recherche médicale, Paris, France
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43
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Critical role of Myc activation in mouse hepatocarcinogenesis induced by the activation of AKT and RAS pathways. Oncogene 2017; 36:5087-5097. [PMID: 28481866 PMCID: PMC5596209 DOI: 10.1038/onc.2017.114] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 02/27/2017] [Accepted: 03/18/2017] [Indexed: 12/13/2022]
Abstract
MYC activation at modest levels has been frequently found in hepatocellular carcinoma. However, its significance in hepatocarcinogenesis has remained obscure. Here we examined the role of Myc activation in mouse liver tumours induced by hepatocytic expression of myristoylated AKT (AKT) and/or mutant HRASV12 (HRAS) via transposon-mediated gene integration. AKT or HRAS alone required 5 months to induce liver tumours, whereas their combination generated hepatocellular carcinoma within 8 weeks. Co-introduction of AKT and HRAS induced lipid-laden preneoplastic cells that grew into nodules composed of tumour cells with or without intracytoplasmic lipid, with the latter being more proliferative and associated with spontaneous Myc expression. AKT/HRAS-induced tumorigenesis was almost completely abolished when MadMyc, a competitive Myc inhibitor, was expressed simultaneously. The Tet-On induction of MadMyc in preneoplastic cells significantly inhibited the progression of AKT/HRAS-induced tumours; its induction in transformed cells suppressed their proliferative activity with alterations in lipid metabolism and protein translation. Transposon-mediated Myc overexpression facilitated tumorigenesis by AKT or HRAS, and when it was co-introduced with AKT and HRAS, diffusely infiltrating tumours without lipid accumulation developed as early as 2 weeks. Examination of the dose-responses of Myc in the enhancement of AKT/HRAS-induced tumorigenesis revealed that a reduction to one-third retained enhancing effect but three-times greater introduction damped the process with increased apoptosis. Myc overexpression suppressed the mRNA expression of proteins involved in the synthesis of fatty acids, and when combined with HRAS introduction, it also suppressed the mRNA expression of proteins involved in their degradation. Finally, the MYC-positive human hepatocellular carcinoma was characterized by the cytoplasm devoid of lipid accumulation, prominent nucleoli and a higher proliferative activity. Our results demonstrate that in hepatocarcinogenesis induced by both activated AKT and HRAS, activation of endogenous Myc is an enhancing factor and adequate levels of Myc deregulation further facilitate the process with alterations in cellular metabolism.
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44
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Tao T, Sondalle SB, Shi H, Zhu S, Perez-Atayde AR, Peng J, Baserga SJ, Look AT. The pre-rRNA processing factor DEF is rate limiting for the pathogenesis of MYCN-driven neuroblastoma. Oncogene 2017; 36:3852-3867. [PMID: 28263972 PMCID: PMC5501763 DOI: 10.1038/onc.2016.527] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 12/08/2016] [Accepted: 12/22/2016] [Indexed: 02/07/2023]
Abstract
The nucleolar factor, digestive organ expansion factor (DEF), has a key role in ribosome biogenesis, functioning in pre-ribosomal RNA (pre-rRNA) processing as a component of the small ribosomal subunit (SSU) processome. Here we show that the peripheral sympathetic nervous system (PSNS) is very underdeveloped in def-deficient zebrafish, and that def haploinsufficiency significantly decreases disease penetrance and tumor growth rate in a MYCN-driven transgenic zebrafish model of neuroblastoma that arises in the PSNS. Consistent with these findings, DEF is highly expressed in human neuroblastoma, and its depletion in human neuroblastoma cell lines induces apoptosis. Interestingly, overexpression of MYCN in zebrafish and in human neuroblastoma cells results in the appearance of intermediate pre-rRNAs species that reflect the processing of pre-rRNAs through Pathway 2, a pathway that processes pre-rRNAs in a different temporal order than the more often used Pathway 1. Our results indicate that DEF and possibly other components of the SSU processome provide a novel site of vulnerability in neuroblastoma cells that could be exploited for targeted therapy.
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Affiliation(s)
- T Tao
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - S B Sondalle
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - H Shi
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.,College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - S Zhu
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Mayo Clinic Cancer Center and Mayo Clinic Center for Individualized Medicine, Rochester, MN, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Mayo Clinic Cancer Center and Mayo Clinic Center for Individualized Medicine, Rochester, MN, USA
| | - A R Perez-Atayde
- Department of Pathology, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | - J Peng
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - S J Baserga
- Departments of Molecular Biophysics &Biochemistry, Genetics and Therapeutic Radiology, Yale University and Yale University School of Medicine, New Haven, CT, USA
| | - A T Look
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
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45
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Whitfield JR, Beaulieu ME, Soucek L. Strategies to Inhibit Myc and Their Clinical Applicability. Front Cell Dev Biol 2017; 5:10. [PMID: 28280720 PMCID: PMC5322154 DOI: 10.3389/fcell.2017.00010] [Citation(s) in RCA: 218] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 02/03/2017] [Indexed: 12/20/2022] Open
Abstract
Myc is an oncogene deregulated in most-perhaps all-human cancers. Each Myc family member, c-, L-, and N-Myc, has been connected to tumor progression and maintenance. Myc is recognized as a "most wanted" target for cancer therapy, but has for many years been considered undruggable, mainly due to its nuclear localization, lack of a defined ligand binding site, and physiological function essential to the maintenance of normal tissues. The challenge of identifying a pharmacophore capable of overcoming these hurdles is reflected in the current absence of a clinically-viable Myc inhibitor. The first attempts to inhibit Myc used antisense technology some three decades ago, followed by small molecule inhibitors discovered through "classical" compound library screens. Notable breakthroughs proving the feasibility of systemic Myc inhibition were made with the Myc dominant negative mutant Omomyc, showing both the great promise in targeting this infamous oncogene for cancer treatment as well as allaying fears about the deleterious side effects that Myc inhibition might have on normal proliferating tissues. During this time many other strategies have appeared in an attempt to drug the undruggable, including direct and indirect targeting, knockdown, protein/protein and DNA interaction inhibitors, and translation and expression regulation. The inhibitors range from traditional small molecules to natural chemicals, to RNA and antisense, to peptides and miniproteins. Here, we briefly describe the many approaches taken so far, with a particular focus on their potential clinical applicability.
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Affiliation(s)
- Jonathan R Whitfield
- Vall d'Hebron Institute of Oncology, Edifici Cellex, Hospital Vall d'Hebron Barcelona, Spain
| | | | - Laura Soucek
- Vall d'Hebron Institute of Oncology, Edifici Cellex, Hospital Vall d'HebronBarcelona, Spain; Peptomyc, Edifici Cellex, Hospital Vall d'HebronBarcelona, Spain; Institució Catalana de Recerca i Estudis AvançatsBarcelona, Spain; Department of Biochemistry and Molecular Biology, Universitat Autònoma de BarcelonaBellaterra, Spain
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46
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The Potential of Targeting Ribosome Biogenesis in High-Grade Serous Ovarian Cancer. Int J Mol Sci 2017; 18:ijms18010210. [PMID: 28117679 PMCID: PMC5297839 DOI: 10.3390/ijms18010210] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/07/2017] [Accepted: 01/12/2017] [Indexed: 02/06/2023] Open
Abstract
Overall survival for patients with ovarian cancer (OC) has shown little improvement for decades meaning new therapeutic options are critical. OC comprises multiple histological subtypes, of which the most common and aggressive subtype is high-grade serous ovarian cancer (HGSOC). HGSOC is characterized by genomic structural variations with relatively few recurrent somatic mutations or dominantly acting oncogenes that can be targeted for the development of novel therapies. However, deregulation of pathways controlling homologous recombination (HR) and ribosome biogenesis has been observed in a high proportion of HGSOC, raising the possibility that targeting these basic cellular processes may provide improved patient outcomes. The poly (ADP-ribose) polymerase (PARP) inhibitor olaparib has been approved to treat women with defects in HR due to germline BRCA mutations. Recent evidence demonstrated the efficacy of targeting ribosome biogenesis with the specific inhibitor of ribosomal RNA synthesis, CX-5461 in v-myc avian myelocytomatosis viral oncogene homolog (MYC)-driven haematological and prostate cancers. CX-5461 has now progressed to a phase I clinical trial in patients with haematological malignancies and phase I/II trial in breast cancer. Here we review the currently available targeted therapies for HGSOC and discuss the potential of targeting ribosome biogenesis as a novel therapeutic approach against HGSOC.
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Cell cycle and growth stimuli regulate different steps of RNA polymerase I transcription. Gene 2016; 612:36-48. [PMID: 27989772 DOI: 10.1016/j.gene.2016.12.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 12/09/2016] [Accepted: 12/14/2016] [Indexed: 12/20/2022]
Abstract
Transcription of the ribosomal RNA genes (rDNA) by RNA polymerase I (Pol I) is a major control step for ribosome synthesis and is tightly linked to cellular growth. However, the question of whether this process is modulated primarily at the level of transcription initiation or elongation is controversial. Studies in markedly different cell types have identified either initiation or elongation as the major control point. In this study, we have re-examined this question in NIH3T3 fibroblasts using a combination of metabolic labeling of the 47S rRNA, chromatin immunoprecipitation analysis of Pol I and overexpression of the transcription initiation factor Rrn3. Acute manipulation of growth factor levels altered rRNA synthesis rates over 8-fold without changing Pol I loading onto the rDNA. In fact, robust changes in Pol I loading were only observed under conditions where inhibition of rDNA transcription was associated with chronic serum starvation or cell cycle arrest. Overexpression of the transcription initiation factor Rrn3 increased loading of Pol I on the rDNA but failed to enhance rRNA synthesis in either serum starved, serum treated or G0/G1 arrested cells. Together these data suggest that transcription elongation is rate limiting for rRNA synthesis. We propose that transcription initiation is required for rDNA transcription in response to cell cycle cues, whereas elongation controls the dynamic range of rRNA synthesis output in response to acute growth factor modulation.
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Tafur L, Sadian Y, Hoffmann NA, Jakobi AJ, Wetzel R, Hagen WJH, Sachse C, Müller CW. Molecular Structures of Transcribing RNA Polymerase I. Mol Cell 2016; 64:1135-1143. [PMID: 27867008 PMCID: PMC5179497 DOI: 10.1016/j.molcel.2016.11.013] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/26/2016] [Accepted: 11/04/2016] [Indexed: 01/22/2023]
Abstract
RNA polymerase I (Pol I) is a 14-subunit enzyme that solely synthesizes pre-ribosomal RNA. Recently, the crystal structure of apo Pol I gave unprecedented insight into its molecular architecture. Here, we present three cryo-EM structures of elongating Pol I, two at 4.0 Å and one at 4.6 Å resolution, and a Pol I open complex at 3.8 Å resolution. Two modules in Pol I mediate the narrowing of the DNA-binding cleft by closing the clamp domain. The DNA is bound by the clamp head and by the protrusion domain, allowing visualization of the upstream and downstream DNA duplexes in one of the elongation complexes. During formation of the Pol I elongation complex, the bridge helix progressively folds, while the A12.2 C-terminal domain is displaced from the active site. Our results reveal the conformational changes associated with elongation complex formation and provide additional insight into the Pol I transcription cycle. Pol I gradually closes its DNA-binding cleft during elongation complex formation Pol I bridge helix folds into a conformation similar to that in other RNA polymerases During elongation, the Pol I A12.2 C-terminal domain is excluded from the cleft A49 tandem winged helix domain contacts upstream DNA, similar to TFIIE
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Affiliation(s)
- Lucas Tafur
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Yashar Sadian
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Niklas A Hoffmann
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Arjen J Jakobi
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany; European Molecular Biology Laboratory (EMBL), Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Rene Wetzel
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Wim J H Hagen
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Carsten Sachse
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Christoph W Müller
- European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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Brighenti E, Treré D, Derenzini M. Targeted cancer therapy with ribosome biogenesis inhibitors: a real possibility? Oncotarget 2016; 6:38617-27. [PMID: 26415219 PMCID: PMC4770724 DOI: 10.18632/oncotarget.5775] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/04/2015] [Indexed: 12/13/2022] Open
Abstract
The effects of many chemotherapeutic drugs on ribosome biogenesis have been underestimated for a long time. Indeed, many drugs currently used for cancer treatment--and which are known to either damage DNA or hinder DNA synthesis--have been shown to exert their toxic action mainly by inhibiting rRNA synthesis or maturation. Moreover, there are new drugs that have been proposed recently for cancer chemotherapy, which only hinder ribosome biogenesis without any genotoxic activity. Even though ribosome biogenesis occurs in both normal and cancer cells, whether resting or proliferating, there is evidence that the selective inhibition of ribosome biogenesis may, in some instances, result in a selective damage to neoplastic cells. The higher sensitivity of cancer cells to inhibitors of rRNA synthesis appears to be the consequence of either the loss of the mechanisms controlling the cell cycle progression or the acquisition of activating oncogene and inactivating tumor suppressor gene mutations that up-regulate the ribosome biogenesis rate. This article reviews those cancer cell characteristics on which the selective cancer cell cytotoxicity induced by the inhibitors of ribosome biogenesis is based.
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Affiliation(s)
- Elisa Brighenti
- Department of Experimental, Diagnostic and Specialty Medicine, Bologna University, Bologna, Italy
| | - Davide Treré
- Department of Experimental, Diagnostic and Specialty Medicine, Bologna University, Bologna, Italy
| | - Massimo Derenzini
- Department of Experimental, Diagnostic and Specialty Medicine, Bologna University, Bologna, Italy
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Harper JW, Bennett EJ. Proteome complexity and the forces that drive proteome imbalance. Nature 2016; 537:328-38. [PMID: 27629639 DOI: 10.1038/nature19947] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/29/2016] [Indexed: 12/28/2022]
Abstract
The cellular proteome is a complex microcosm of structural and regulatory networks that requires continuous surveillance and modification to meet the dynamic needs of the cell. It is therefore crucial that the protein flux of the cell remains in balance to ensure proper cell function. Genetic alterations that range from chromosome imbalance to oncogene activation can affect the speed, fidelity and capacity of protein biogenesis and degradation systems, which often results in proteome imbalance. An improved understanding of the causes and consequences of proteome imbalance is helping to reveal how these systems can be targeted to treat diseases such as cancer.
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Affiliation(s)
- J Wade Harper
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Eric J Bennett
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093, USA
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