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Graham MK, Xu B, Davis C, Meeker AK, Heaphy CM, Yegnasubramanian S, Dyer MA, Zeineldin M. The TERT Promoter is Polycomb-Repressed in Neuroblastoma Cells with Long Telomeres. CANCER RESEARCH COMMUNICATIONS 2024; 4:1533-1547. [PMID: 38837897 PMCID: PMC11188873 DOI: 10.1158/2767-9764.crc-22-0287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 05/04/2023] [Accepted: 05/22/2024] [Indexed: 06/07/2024]
Abstract
Acquiring a telomere maintenance mechanism is a hallmark of high-risk neuroblastoma and commonly occurs by expressing telomerase (TERT). Telomerase-negative neuroblastoma has long telomeres and utilizes the telomerase-independent alternative lengthening of telomeres (ALT) mechanism. Conversely, no discernable telomere maintenance mechanism is detected in a fraction of neuroblastoma with long telomeres. Here, we show, unlike most cancers, DNA of the TERT promoter is broadly hypomethylated in neuroblastoma. In telomerase-positive neuroblastoma cells, the hypomethylated DNA promoter is approximately 1.5 kb. The TERT locus shows active chromatin marks with low enrichment for the repressive mark, H3K27me3. MYCN, a commonly amplified oncogene in neuroblstoma, binds to the promoter and induces TERT expression. Strikingly, in neuroblastoma with long telomeres, the hypomethylated region spans the entire TERT locus, including multiple nearby genes with enrichment for the repressive H3K27me3 chromatin mark. Furthermore, subtelomeric regions showed enrichment of repressive chromatin marks in neuroblastomas with long telomeres relative to those with short telomeres. These repressive marks were even more evident at the genic loci, suggesting a telomere position effect (TPE). Inhibiting H3K27 methylation by three different EZH2 inhibitors induced the expression of TERT in cell lines with long telomeres and H3K27me3 marks in the promoter region. EZH2 inhibition facilitated MYCN binding to the TERT promoter in neuroblastoma cells with long telomeres. Taken together, these data suggest that epigenetic regulation of TERT expression differs in neuroblastoma depending on the telomere maintenance status, and H3K27 methylation is important in repressing TERT expression in neuroblastoma with long telomeres. SIGNIFICANCE The epigenetic landscape of the TERT locus is unique in neuroblastoma. The DNA at the TERT locus, unlike other cancer cells and similar to normal cells, are hypomethylated in telomerase-positive neuroblastoma cells. The TERT locus is repressed by polycomb repressive complex-2 complex in neuroblastoma cells that have long telomeres and do not express TERT. Long telomeres in neuroblastoma cells are also associated with repressive chromatin states at the chromosomal termini, suggesting TPE.
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Affiliation(s)
- Mindy K. Graham
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Urology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
| | - Beisi Xu
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Christine Davis
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Alan K. Meeker
- Department of Urology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Christopher M. Heaphy
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Srinivasan Yegnasubramanian
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Michael A. Dyer
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee
- Howard Hughes Medical Institute, Chevy Chase, Maryland
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Maged Zeineldin
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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2
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Ng YB, Akincilar SC. Shaping DNA damage responses: Therapeutic potential of targeting telomeric proteins and DNA repair factors in cancer. Curr Opin Pharmacol 2024; 76:102460. [PMID: 38776747 DOI: 10.1016/j.coph.2024.102460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 10/06/2023] [Accepted: 10/11/2023] [Indexed: 05/25/2024]
Abstract
Shelterin proteins regulate genomic stability by preventing inappropriate DNA damage responses (DDRs) at telomeres. Unprotected telomeres lead to persistent DDR causing cell cycle inhibition, growth arrest, and apoptosis. Cancer cells rely on DDR to protect themselves from DNA lesions and exogenous DNA-damaging agents such as chemotherapy and radiotherapy. Therefore, targeting DDR machinery is a promising strategy to increase the sensitivity of cancer cells to existing cancer therapies. However, the success of these DDR inhibitors depends on other mutations, and over time, patients develop resistance to these therapies. This suggests the need for alternative approaches. One promising strategy is co-inhibiting shelterin proteins with DDR molecules, which would offset cellular fitness in DNA repair in a mutation-independent manner. This review highlights the associations and dependencies of the shelterin complex with the DDR proteins and discusses potential co-inhibition strategies that might improve the therapeutic potential of current inhibitors.
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Affiliation(s)
- Yu Bin Ng
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A∗STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
| | - Semih Can Akincilar
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A∗STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore.
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3
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Han T, Geng YQ, Zhang M, Cao Y, Zhu JJ. Aggregation-Induced Enhanced Electrochemiluminescence from Tris(bipyridine)ruthenium(II) Derivative Nanosheets for the Ultrasensitive Detection of Human Telomerase RNA. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2306291. [PMID: 37775937 DOI: 10.1002/smll.202306291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/16/2023] [Indexed: 10/01/2023]
Abstract
The traditional tris(bipyridine)ruthenium(II) complex suffers from the notorious aggregation-caused quenching effect, which greatly compromises its electrochemiluminescence (ECL) efficiency, thus hindering further applications in biosensing and clinical diagnosis. Here, the ultrathin tetraphenylethylene-active tris(bipyridine)ruthenium(II) derivative nanosheets (abbreviated as Ru-TPE NSs) are synthesized through a protein-assisted self-assembly strategy for ultrasensitive ECL detection of human telomerase RNA (hTR) for the first time. The synthesized Ru-TPE NSs exhibit the aggregation-induced enhanced ECL behavior and excellent water-dispersion. Surprisingly, up to a 106.5-fold increase in the ECL efficiency of Ru-TPE NSs is demonstrated compared with the dispersed molecules in an organic solution. The restriction of intramolecular motions is confirmed to be responsible for the significant ECL enhancement. Therefore, this proposed ECL biosensor shows high sensitivity and excellent selectivity for hTR based on Ru-TPE NSs as efficient ECL beacons and the catalytic hairpin assembly as signal amplification, whose detection limit is as low as 8.0 fm, which is far superior to the previously reported works. Here, a promising analytical method is provided for early clinical diagnosis and a new type of efficient ECL emitters with great application prospects is represented.
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Affiliation(s)
- Tingting Han
- Jiangsu Key Laboratory of Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology/Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, 210014, Nanjing, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Yu-Qian Geng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Min Zhang
- Guangdong Engineering and Technology Research Center for Advanced Nanomaterials, School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, P. R. China
| | - Yue Cao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Jun-Jie Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
- Guangdong Engineering and Technology Research Center for Advanced Nanomaterials, School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, P. R. China
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4
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Zade NH, Khattar E. POT1 mutations cause differential effects on telomere length leading to opposing disease phenotypes. J Cell Physiol 2023; 238:1237-1255. [PMID: 37183325 DOI: 10.1002/jcp.31034] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/28/2023] [Accepted: 04/17/2023] [Indexed: 05/16/2023]
Abstract
The protection of telomere protein (POT1) is a telomere-binding protein and is an essential component of the six-membered shelterin complex, which is associated with the telomeres. POT1 directly binds to the 3' single-stranded telomeric overhang and prevents the activation of DNA damage response at telomeres thus preventing the telomere-telomere fusions and genomic instability. POT1 also plays a pivotal role in maintaining telomere length by regulating telomerase-mediated telomere elongation. Mutations in POT1 proteins result in three different telomere phenotypes, which include long, short, or aberrant telomere length. Long telomeres predispose individuals to cancer, while short or aberrant telomere phenotypes result in pro-aging diseases referred to as telomeropathies. Here, we review the function of POT1 proteins in telomere length hemostasis and how the spectrum of mutations reported in POT1 can be segregated toward developing very distinct disease phenotypes of cancer and telomeropathies.
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Affiliation(s)
- Nikita Harish Zade
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, India
| | - Ekta Khattar
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, India
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5
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Saretzki G. Measuring telomerase activity using TRAP assays. Methods Cell Biol 2023; 181:127-149. [PMID: 38302235 DOI: 10.1016/bs.mcb.2022.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Telomerase is a reverse transcriptase that consists of the telomerase reverse transcriptase (TERT) protein and the telomerase RNA component TERC which also harbors the template region for telomere synthesis. In its canonical function the enzyme adds single-stranded telomeric hexanucleotides de novo to the ends of linear chromosomes, telomeres, in telomerase-positive cells such as germline, stem- and cancer cells. This potential biochemical activity of telomerase can be measured with the help of a telomerase repeat amplification protocol (TRAP) which often includes a PCR amplification due to the low abundance of telomerase in most cells and tissues. The current chapter describes various TRAP methods to detect telomerase activity (TA) using gel-based methods, its advantages and deficits, how to perform an ELISA-based TRAP assay and how best to interpret its results. Since development of the TRAP assay in 1994, there have been numerous modifications and adaptations of the method from real-time PCR analysis, isothermal amplification and nanotechnology to CRISPR/Cas-based methods which will be briefly mentioned. However, it is not possible to cover all different TRAP methods and thus there is no comprehensiveness claimed by this chapter. Instead, the author describes various aspects of using TRAP assays including required controls, sample preparation, etc. in order to avoid pitfalls and set-backs in applying this rather complex and demanding technique. The TRAP assay is particularly important to support clinical diagnosis of cancer, analyze tumor therapy as well as to evaluate various approaches to inhibit TA as a form of anti-cancer therapy.
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Affiliation(s)
- Gabriele Saretzki
- Biosciences Institute, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.
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6
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Song J, Li S, Jie Z, Qiao Y, Yang XJ, Chen HY, Xu JJ. Triple signal amplification strategy for ultrasensitive in situ imaging of intracellular telomerase RNA. Anal Chim Acta 2023; 1256:341145. [PMID: 37037628 DOI: 10.1016/j.aca.2023.341145] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/01/2023] [Accepted: 03/23/2023] [Indexed: 03/30/2023]
Abstract
Abnormal upregulation of telomerase RNA (TR) is a hallmark event at various stages of tumor progression, providing a universal marker for early diagnosis of cancer. Here, we have developed a triple signal amplification strategy for in situ visualization of TR in living cells, which sequentially incorporated the target-initiated strand displacement circuit, multidirectional rolling circle amplification (RCA), and Mg2+ DNAzyme-mediated amplification. All oligonucleotide probes and cofactors were transfected into cells in one go, and then escaped from lysosomes successfully. Owing to the specific base pairing, the amplification cascades could only be triggered by TR and performed as programmed, resulting in a satisfactory signal-to-background ratio. Especially, the netlike DNA structure generated by RCA encapsulated high concentrations of DNAzyme and substrates (FQS) in a local region, thereby improving the reaction efficiency and kinetics of the third amplification cycle. Under optimal conditions, the proposed method exhibited ultrasensitive detection of TR mimic with a detection limit at pM level. Most importantly, after transfection with the proposed sensing platform, tumor cells can be easily distinguished from normal cells based on TR abundance-related fluorescence signal, providing a new insight into initial cancer screening.
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7
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Vinayagamurthy S, Bagri S, Mergny JL, Chowdhury S. Telomeres expand sphere of influence: emerging molecular impact of telomeres in non-telomeric functions. Trends Genet 2023; 39:59-73. [PMID: 36404192 PMCID: PMC7614491 DOI: 10.1016/j.tig.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 09/12/2022] [Accepted: 10/26/2022] [Indexed: 11/18/2022]
Abstract
Although the impact of telomeres on physiology stands well established, a question remains: how do telomeres impact cellular functions at a molecular level? This is because current understanding limits the influence of telomeres to adjacent subtelomeric regions despite the wide-ranging impact of telomeres. Emerging work in two distinct aspects offers opportunities to bridge this gap. First, telomere-binding factors were found with non-telomeric functions. Second, locally induced DNA secondary structures called G-quadruplexes are notably abundant in telomeres, and gene regulatory regions genome wide. Many telomeric factors bind to G-quadruplexes for non-telomeric functions. Here we discuss a more general model of how telomeres impact the non-telomeric genome - through factors that associate at telomeres and genome wide - and influence cell-intrinsic functions, particularly aging, cancer, and pluripotency.
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Affiliation(s)
- Soujanya Vinayagamurthy
- Integrative and Functional Biology Unit, CSIR Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Sulochana Bagri
- Integrative and Functional Biology Unit, CSIR Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Jean-Louis Mergny
- Institute of Biophysics of the CAS, v.v.i. Královopolská 135, 612 65 Brno, Czech Republic; Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Shantanu Chowdhury
- Integrative and Functional Biology Unit, CSIR Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; GNR Knowledge Centre for Genome and Informatics, CSIR Institute of Genomics and Integrative Biology, New Delhi 110025, India.
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8
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Judasz E, Lisiak N, Kopczyński P, Taube M, Rubiś B. The Role of Telomerase in Breast Cancer's Response to Therapy. Int J Mol Sci 2022; 23:12844. [PMID: 36361634 PMCID: PMC9654063 DOI: 10.3390/ijms232112844] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 10/13/2022] [Accepted: 10/24/2022] [Indexed: 11/26/2023] Open
Abstract
Currently, breast cancer appears to be the most widespread cancer in the world and the most common cause of cancer deaths. This specific type of cancer affects women in both developed and developing countries. Prevention and early diagnosis are very important factors for good prognosis. A characteristic feature of cancer cells is the ability of unlimited cell division, which makes them immortal. Telomeres, which are shortened with each cell division in normal cells, are rebuilt in cancer cells by the enzyme telomerase, which is expressed in more than 85% of cancers (up to 100% of adenocarcinomas, including breast cancer). Telomerase may have different functions that are related to telomeres or unrelated. It has been shown that high activity of the enzyme in cancer cells is associated with poor cell sensitivity to therapies. Therefore, telomerase has become a potential target for cancer therapies. The low efficacy of therapies has resulted in the search for new combined and more effective therapeutic methods, including the involvement of telomerase inhibitors and telomerase-targeted immunotherapy.
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Affiliation(s)
- Eliza Judasz
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Natalia Lisiak
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Przemysław Kopczyński
- Centre for Orthodontic Mini-Implants at the Department and Clinic of Maxillofacial Orthopedics and Orthodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
| | - Magdalena Taube
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 60-806 Poznan, Poland
| | - Błażej Rubiś
- Department of Clinical Chemistry and Molecular Diagnostics, Poznan University of Medical Sciences, 60-806 Poznan, Poland
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9
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Liu Y, Betori RC, Pagacz J, Frost GB, Efimova EV, Wu D, Wolfgeher DJ, Bryan TM, Cohen SB, Scheidt KA, Kron SJ. Targeting telomerase reverse transcriptase with the covalent inhibitor NU-1 confers immunogenic radiation sensitization. Cell Chem Biol 2022; 29:1517-1531.e7. [PMID: 36206753 PMCID: PMC9588800 DOI: 10.1016/j.chembiol.2022.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/29/2022] [Accepted: 09/15/2022] [Indexed: 11/03/2022]
Abstract
Beyond synthesizing telomere repeats, the telomerase reverse transcriptase (TERT) also serves multiple other roles supporting cancer growth. Blocking telomerase to drive telomere erosion appears impractical, but TERT's non-canonical activities have yet to be fully explored as cancer targets. Here, we used an irreversible TERT inhibitor, NU-1, to examine impacts on resistance to conventional cancer therapies. In vitro, inhibiting TERT sensitized cells to chemotherapy and radiation. NU-1 delayed repair of double-strand breaks, resulting in persistent DNA damage signaling and cellular senescence. Although NU-1 alone did not impact growth of syngeneic CT26 tumors in BALB/c mice, it dramatically enhanced the effects of radiation, leading to immune-dependent tumor elimination. Tumors displayed persistent DNA damage, suppressed proliferation, and increased activated immune infiltrate. Our studies confirm TERT's role in limiting genotoxic effects of conventional therapy but also implicate TERT as a determinant of immune evasion and therapy resistance.
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Affiliation(s)
- Yue Liu
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Rick C Betori
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Joanna Pagacz
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Grant B Frost
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Elena V Efimova
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Ding Wu
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Donald J Wolfgeher
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Tracy M Bryan
- Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Scott B Cohen
- Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Karl A Scheidt
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
| | - Stephen J Kron
- Ludwig Center for Metastasis Research and Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA.
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10
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Akıncılar S, Chua J, Ng Q, Chan C, Eslami-S Z, Chen K, Low JL, Arumugam S, Aswad L, Chua C, Tan I, DasGupta R, Fullwood M, Tergaonkar V. Identification of mechanism of cancer-cell-specific reactivation of hTERT offers therapeutic opportunities for blocking telomerase specifically in human colorectal cancer. Nucleic Acids Res 2022; 51:1-16. [PMID: 35697349 PMCID: PMC9841410 DOI: 10.1093/nar/gkac479] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/18/2022] [Accepted: 05/26/2022] [Indexed: 01/29/2023] Open
Abstract
Transcriptional reactivation of hTERT is the limiting step in tumorigenesis. While mutations in hTERT promoter present in 19% of cancers are recognized as key drivers of hTERT reactivation, mechanisms by which wildtype hTERT (WT-hTERT) promoter is reactivated, in majority of human cancers, remain unknown. Using primary colorectal cancers (CRC) we identified Tert INTeracting region 2 (T-INT2), the critical chromatin region essential for reactivating WT-hTERT promoter in CRCs. Elevated β-catenin and JunD level in CRC facilitates chromatin interaction between hTERT promoter and T-INT2 that is necessary to turn on hTERTexpression. Pharmacological screens uncovered salinomycin, which inhibits JunD mediated hTERT-T-INT2 interaction that is required for the formation of a stable transcription complex on the hTERT promoter. Our results showed for the first time how known CRC alterations, such as APC, lead to WT-hTERT promoter reactivation during stepwise-tumorigenesis and provide a new perspective for developing cancer-specific drugs.
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Affiliation(s)
- Semih Can Akıncılar
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Joelle Yi Heng Chua
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Qin Feng Ng
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Claire Hian Tzer Chan
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Zahra Eslami-S
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Kaijing Chen
- Cancer Science Institute of Singapore, National University of Singapore, 117599, Singapore
| | - Joo-Leng Low
- Laboratory of Precision Oncology and Cancer Evolution, Genome Institute of Singapore, A*STAR, 138672, Singapore
| | - Surendar Arumugam
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 138673, Singapore
| | - Luay Aswad
- Cancer Science Institute of Singapore, National University of Singapore, 117599, Singapore
| | - Clarinda Chua
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), 138672, Singapore,Department of Medical Oncology, National Cancer Centre Singapore, 169610, Singapore
| | - Iain Beehuat Tan
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), 138672, Singapore,Department of Medical Oncology, National Cancer Centre Singapore, 169610, Singapore
| | - Ramanuj DasGupta
- Laboratory of Precision Oncology and Cancer Evolution, Genome Institute of Singapore, A*STAR, 138672, Singapore
| | - Melissa Jane Fullwood
- Cancer Science Institute of Singapore, National University of Singapore, 117599, Singapore,School of Biological Sciences, Nanyang Technological University, 637551, Singapore
| | - Vinay Tergaonkar
- To whom correspondence should be addressed. Tel: +65 65869836; Fax: +65 67791117;
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11
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Mirzaei S, Saghari S, Bassiri F, Raesi R, Zarrabi A, Hushmandi K, Sethi G, Tergaonkar V. NF-κB as a regulator of cancer metastasis and therapy response: A focus on epithelial-mesenchymal transition. J Cell Physiol 2022; 237:2770-2795. [PMID: 35561232 DOI: 10.1002/jcp.30759] [Citation(s) in RCA: 82] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/24/2022] [Accepted: 04/19/2022] [Indexed: 12/13/2022]
Abstract
Metastasis of tumor cells is a complex challenge and significantly diminishes the overall survival and prognosis of cancer patients. The epithelial-to-mesenchymal transition (EMT) is a well-known mechanism responsible for the invasiveness of tumor cells. A number of molecular pathways can regulate the EMT mechanism in cancer cells and nuclear factor-kappaB (NF-κB) is one of them. The nuclear translocation of NF-κB p65 can induce the transcription of several genes involved in EMT induction. The present review describes NF-κB and EMT interaction in cancer cells and their association in cancer progression. Due to the oncogenic role NF-κB signaling, its activation enhances metastasis of tumor cells via EMT induction. This has been confirmed in various cancers including brain, breast, lung and gastric cancers, among others. The ZEB1/2, transforming growth factor-β, and Slug as inducers of EMT undergo upregulation by NF-κB to promote metastasis of tumor cells. After EMT induction driven by NF-κB, a significant decrease occurs in E-cadherin levels, while N-cadherin and vimentin levels undergo an increase. The noncoding RNAs can potentially also function as upstream mediators and modulate NF-κB/EMT axis in cancers. Moreover, NF-κB/EMT axis is involved in mediating drug resistance in tumor cells. Thus, suppressing NF-κB/EMT axis can also promote the sensitivity of cancer cells to chemotherapeutic agents.
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Affiliation(s)
- Sepideh Mirzaei
- Department of Biology, Faculty of Science, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Sam Saghari
- Department of Health Services Management, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Farzaneh Bassiri
- Department of Biology, Fars Science and Research Branch, Islamic Azad University, Fars, Iran.,Department of Biology, Shiraz Branch, Islamic Azad University, Shiraz, Iran
| | - Rasoul Raesi
- PhD in Health Services Management, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Zarrabi
- Department of Biomedical Engineering, Faculty of Engineering and Natural Sciences, Istinye University, Istanbul, Turkey
| | - Kiavash Hushmandi
- Department of Food Hygiene and Quality Control, Division of Epidemiology and Zoonoses, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Yong Loo Lin School of Medicine, NUS Centre for Cancer Research (N2CR), National University of Singapore, Singapore, Singapore
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore, Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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12
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Zhang B, Shi L, Li B, Jin Y. Ratiometric fluorescence resonance energy transfer for reliable and sensitive detection of intracellular telomerase RNA via strand displacement reaction amplification. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 271:120937. [PMID: 35114633 DOI: 10.1016/j.saa.2022.120937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Human telomerase RNA (hTR) is one essential component of telomerase and is overexpressed in tumor cells. Therefore, the reliable and sensitive detection of hTR is essential for the early cancer diagnosis. Herein, to avoid the false positive signals caused by co-existing components in the cell, a ratiometric fluorescence resonance energy transfer (FRET) strategy was developed to achieve reliable detection of intracellular hTR. Manganese dioxide nanosheets (MnO2NS) with good biocompatibility carry two fluorophore-labelled hairpin DNA probes into the cancer cell and then release the probes via decomposition of MnO2NS by intracellular L-glutathione reduced (GSH). Then, hTR triggered the cyclic strand displacement reaction (SDR) between two hairpin DNA probes to continuously form DNA duplexes, which made two fluorophores close to each other and led to an effective FRET. Fluorescence imaging demonstrated a higher expression level of hTR in HeLa cells than that in normal HL-7702 cells. The high specificity of hairpin DNA probes and SDR make it easy to discriminate the single-base mutation. Therefore, it provides a highly sensitive, simple and reliable method for the extracellular and intracellular detection of hTR.
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Affiliation(s)
- Bei Zhang
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China
| | - Lu Shi
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China
| | - Baoxin Li
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China
| | - Yan Jin
- Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
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13
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Genome-wide screens identify specific drivers of mutant hTERT promoters. Proc Natl Acad Sci U S A 2022; 119:2105171119. [PMID: 35027447 PMCID: PMC8784157 DOI: 10.1073/pnas.2105171119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2021] [Indexed: 12/31/2022] Open
Abstract
Mutations in hTERT promoter are seen in over 19% of human cancers, irrespective of the cancer type. Understanding the molecular players that regulate Mut-hTERT promoters may help the design of effective targeting strategies to inhibit telomerase reactivation specifically in cancer cells. Our work uses genome-wide functional screens to identify 30 specific regulators of Mut-hTERT promoters. These candidates identified from the screening serve as an excellent resource to understand how telomerase is reactivated and as targets for making inhibitors to telomerase, a key driver of cancer. Cancer-specific hTERT promoter mutations reported in 19% of cancers result in enhanced telomerase activity. Understanding the distinctions between transcriptional regulation of wild-type (WT) and mutant (Mut) hTERT promoters may open up avenues for development of inhibitors which specially block hTERT expression in cancer cells. To comprehensively identify physiological regulators of WT- or Mut-hTERT promoters, we generated several isogenic reporter cells driven by endogenous hTERT loci. Genome-wide CRISPR-Cas9 and small interfering RNA screens using these isogenic reporter lines identified specific regulators of Mut-hTERT promoters. We validate and characterize one of these hits, namely, MED12, a kinase subunit of mediator complex. We demonstrate that MED12 specifically drives expression of hTERT from the Mut-hTERT promoter by mediating long-range chromatin interaction between the proximal Mut-hTERT promoter and T-INT1 distal regulatory region 260 kb upstream. Several hits identified in our screens could serve as potential therapeutic targets, inhibition of which may specifically block Mut-hTERT promoter driven telomerase reactivation in cancers.
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14
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Unraveling B cell trajectories at single cell resolution. Trends Immunol 2022; 43:210-229. [DOI: 10.1016/j.it.2022.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/03/2022] [Accepted: 01/04/2022] [Indexed: 12/31/2022]
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15
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Siddiqui A, Shah Z, Jahan RN, Othman I, Kumari Y. Mechanistic role of boswellic acids in Alzheimer's disease: Emphasis on anti-inflammatory properties. Biomed Pharmacother 2021; 144:112250. [PMID: 34607104 DOI: 10.1016/j.biopha.2021.112250] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/17/2021] [Accepted: 09/26/2021] [Indexed: 12/24/2022] Open
Abstract
The resin/gum of Boswellia species belonging to the family of Burseraceae is a naturally occurring mixture of bioactive compounds, which was traditionally used as a folk medicine to treat conditions like chronic inflammation. Several research studies have also explored its' therapeutic potential against multiple neurodegenerative diseases such as Alzheimer's disease (AD). The main chemical constituents of this gum include boswellic acids (BAs) like 3-O-acetyl-11-keto-β boswellic acid (AKBA) that possess potent anti-inflammatory and neuroprotective properties in AD. It is also involved in inhibiting the acetylcholinesterase (AChE) activity in the cholinergic pathway and improve choline levels as well as its binding with nicotinic receptors to produce anti-inflammatory effects. Multiple shreds of evidence have demonstrated that BAs modulate key molecular targets and signalling pathways like 5-lipoxygenase/cyclooxygenase, Nrf2, NF-kB, cholinergic, amyloid-beta (Aβ), and neurofibrillary tangles formation (NFTs) that are involved in AD progression. The present review focuses on the possible mechanistic therapeutic role of BAs in modulating the 5-LOX/COX pathway in arachidonic acid metabolism, activating Nrf2 through binding of ARE, inhibiting NF-kB and AChE activity. In addition, an inhibition of amyloid plaques (Aβ) and neurofibrillary tangles (NFTs) induced neurotoxicity and neuroinflammation in AD by BAs is also discussed in this review. We have also highlighted that BAs possess beneficial effects in AD by targeting multiple molecular pathways and makes it an emerging drug candidate for treating neurodegenerative diseases.
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Affiliation(s)
- Aisha Siddiqui
- Neurological disorder and aging research group (NDA), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500, Selangor, Malaysia
| | - Zahoor Shah
- Department of Medicinal and Biological Chemistry, University of Toledo, 3000 Arlington Avenue, Toledo 43614, OH, USA
| | - Rao Nargis Jahan
- Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard University, New Delhi 110062, India
| | - Iekhsan Othman
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500 Selangor, Malaysia
| | - Yatinesh Kumari
- Neurological disorder and aging research group (NDA), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500, Selangor, Malaysia.
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16
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Subasri M, Shooshtari P, Watson AJ, Betts DH. Analysis of TERT Isoforms across TCGA, GTEx and CCLE Datasets. Cancers (Basel) 2021; 13:cancers13081853. [PMID: 33924498 PMCID: PMC8070023 DOI: 10.3390/cancers13081853] [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: 03/01/2021] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 12/14/2022] Open
Abstract
Reactivation of the multi-subunit ribonucleoprotein telomerase is the primary telomere maintenance mechanism in cancer, but it is rate-limited by the enzymatic component, telomerase reverse transcriptase (TERT). While regulatory in nature, TERT alternative splice variant/isoform regulation and functions are not fully elucidated and are further complicated by their highly diverse expression and nature. Our primary objective was to characterize TERT isoform expression across 7887 neoplastic and 2099 normal tissue samples using The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression Project (GTEx), respectively. We confirmed the global overexpression and splicing shift towards full-length TERT in neoplastic tissue. Stratifying by tissue type we found uncharacteristic TERT expression in normal brain tissue subtypes. Stratifying by tumor-specific subtypes, we detailed TERT expression differences potentially regulated by subtype-specific molecular characteristics. Focusing on β-deletion splicing regulation, we found the NOVA1 trans-acting factor to mediate alternative splicing in a cancer-dependent manner. Of relevance to future tissue-specific studies, we clustered cancer cell lines with tumors from related origin based on TERT isoform expression patterns. Taken together, our work has reinforced the need for tissue and tumour-specific TERT investigations, provided avenues to do so, and brought to light the current technical limitations of bioinformatic analyses of TERT isoform expression.
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Affiliation(s)
- Mathushan Subasri
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (A.J.W.)
| | - Parisa Shooshtari
- Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada;
- Department of Pathology and Laboratory Medicine, The University of Western Ontario, London, ON N6A 5C1, Canada
- Department of Computer Science, The University of Western Ontario, London, ON N6A 5C1, Canada
- The Children’s Health Research Institute—Lawson Health Research Institute, London, ON N6C 2R5, Canada
| | - Andrew J. Watson
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (A.J.W.)
- The Children’s Health Research Institute—Lawson Health Research Institute, London, ON N6C 2R5, Canada
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Dean H. Betts
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (M.S.); (A.J.W.)
- The Children’s Health Research Institute—Lawson Health Research Institute, London, ON N6C 2R5, Canada
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, ON N6A 5C1, Canada
- Correspondence: ; Tel.: +1-519-661-2111 (ext. 83786)
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17
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Regulation of Nuclear Factor-KappaB (NF-κB) signaling pathway by non-coding RNAs in cancer: Inhibiting or promoting carcinogenesis? Cancer Lett 2021; 509:63-80. [PMID: 33838282 DOI: 10.1016/j.canlet.2021.03.025] [Citation(s) in RCA: 159] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/18/2021] [Accepted: 03/24/2021] [Indexed: 12/12/2022]
Abstract
The nuclear factor-kappaB (NF-κB) signaling pathway is considered as a potential therapeutic target in cancer therapy. It has been well established that transcription factor NF-κB is involved in regulating physiological and pathological events including inflammation, immune response and differentiation. Increasing evidences suggest that deregulated NF-κB signaling can enhance cancer cell proliferation, metastasis and also mediate radio-as well as chemo-resistance. On the contrary, non-coding RNAs (ncRNAs) have been found to modulate NF-κB signaling pathway under different settings. MicroRNAs (miRNAs) can dually inhibit/induce NF-κB signaling thereby affecting the growth and migration of cancer cells. Furthermore, the response of cancer cells to radiotherapy and chemotherapy may also be regulated by miRNAs. Regulation of NF-κB by miRNAs may be mediated via binding to 3/-UTR region. Interestingly, anti-tumor compounds can increase the expression of tumor-suppressor miRNAs in inhibiting NF-κB activation and the progression of cancers. Long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) can also effectively modulate NF-κB signaling thus affecting tumorigenesis. It is noteworthy that several studies have demonstrated that lncRNAs and circRNAs can affect miRNAs in targeting NF-κB activation. They can act as competing endogenous RNA (ceRNA) thereby reducing miRNA expression to induce NF-κB activation that can in turn promote cancer progression and malignancy.
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18
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Akincilar SC, Chan CHT, Ng QF, Fidan K, Tergaonkar V. Non-canonical roles of canonical telomere binding proteins in cancers. Cell Mol Life Sci 2021; 78:4235-4257. [PMID: 33599797 PMCID: PMC8164586 DOI: 10.1007/s00018-021-03783-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 12/28/2020] [Accepted: 01/29/2021] [Indexed: 02/06/2023]
Abstract
Reactivation of telomerase is a major hallmark observed in 90% of all cancers. Yet paradoxically, enhanced telomerase activity does not correlate with telomere length and cancers often possess short telomeres; suggestive of supplementary non-canonical roles that telomerase might play in the development of cancer. Moreover, studies have shown that aberrant expression of shelterin proteins coupled with their release from shortening telomeres can further promote cancer by mechanisms independent of their telomeric role. While targeting telomerase activity appears to be an attractive therapeutic option, this approach has failed in clinical trials due to undesirable cytotoxic effects on stem cells. To circumvent this concern, an alternative strategy could be to target the molecules involved in the non-canonical functions of telomeric proteins. In this review, we will focus on emerging evidence that has demonstrated the non-canonical roles of telomeric proteins and their impact on tumorigenesis. Furthermore, we aim to address current knowledge gaps in telomeric protein functions and propose future research approaches that can be undertaken to achieve this.
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Affiliation(s)
- Semih Can Akincilar
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Proteos, 61, Biopolis Drive, Singapore, 138673, Singapore
| | - Claire Hian Tzer Chan
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Proteos, 61, Biopolis Drive, Singapore, 138673, Singapore
| | - Qin Feng Ng
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Proteos, 61, Biopolis Drive, Singapore, 138673, Singapore
| | - Kerem Fidan
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Proteos, 61, Biopolis Drive, Singapore, 138673, Singapore
| | - Vinay Tergaonkar
- Division of Cancer Genetics and Therapeutics, Laboratory of NFκB Signaling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Proteos, 61, Biopolis Drive, Singapore, 138673, Singapore.
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore.
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19
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Long W, Zheng BX, Huang XH, She MT, Liu AL, Zhang K, Wong WL, Lu YJ. Molecular Recognition and Imaging of Human Telomeric G-Quadruplex DNA in Live Cells: A Systematic Advancement of Thiazole Orange Scaffold To Enhance Binding Specificity and Inhibition of Gene Expression. J Med Chem 2021; 64:2125-2138. [PMID: 33559473 DOI: 10.1021/acs.jmedchem.0c01656] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A series of fluorescent ligands, which were systematically constructed from thiazole orange scaffold, was investigated for their interactions with G-quadruplex structures and antitumor activity. Among the ligands, compound 3 was identified to exhibit excellent specificity toward telomere G4-DNA over other nucleic acids. The affinity of 3-Htg24 was almost 5 times higher than that of double-stranded DNA and promoter G4-DNA. Interaction studies showed that 3 may bind to both G-tetrad and the lateral loop near the 5'-end. The intracellular colocalization with BG4 and competition studies with BRACO19 reveal that 3 may interact with G4-structures. Moreover, 3 reduces the telomere length and downregulates hTERC and hTERT mRNA expression in HeLa cells. The cytotoxicity of 3 against cancer cells (IC50 = 12.7-16.2 μM) was found to be generally higher than noncancer cells (IC50 = 52.3 μM). The findings may support that the ligand is telomere G4-DNA specific and may provide meaningful insights for anticancer drug design.
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Affiliation(s)
- Wei Long
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Bo-Xin Zheng
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Xuan-He Huang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Meng-Ting She
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Ao-Lu Liu
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Kun Zhang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China.,School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China
| | - Wing-Leung Wong
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, P. R. China.,State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Yu-Jing Lu
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, P. R. China.,Engineering Research Academy of High Value Utilization of Green Plants, Meizhou 514779, P. R. China
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20
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Abstract
PURPOSE One of the most important serious malignancies is gastric cancer (GC) with a high mortality globally. In this way, beside the environmental factors, genetic parameter has a remarkable effective fluctuation in GC. Correspondingly, telomeres are nucleoprotein structures measuring the length of telomeres and they have special potential in diagnosis of various types of cancers. Defect protection of the telomeric length initiates the instability of the genome during cancer, including gastric cancer. The most common way of maintaining telomere length is the function of the telomerase enzyme that replicates the TTAGGG to the end of the 3' chromosome. METHODS In this review, we want to discuss the alterations of hTERT repression on the modification of TERRA gene expression in conjunction with the importance of telomere and telomerase in GC. RESULTS The telomerase enzyme contains two essential components called telomerase reverse transcriptase (hTERT) and RNA telomerase (hTR, hTERC). Deregulation of hTERT plays a key role in the multistage process of tumorigenicity and anticancer drug resistance. The direct relationship between telomerase activity and hTERT has led to hTERT to be considered a key target for cancer treatment. Recent results show that telomeres are transcribed into telomeric repeat-containing RNA (TERRA) in mammalian cells and are long noncoding RNAs (lncRNAs) identified in different tissues. In addition, most chemotherapy methods have a lot of side effects on normal cells. CONCLUSION Telomere and telomerase are useful therapeutic goal. According to the main roles of hTERT in tumorigenesis, growth, migration, and cancer invasion, hTERT and regulatory mechanisms that control the expression of hTERT are attractive therapeutic targets for cancer treatment.
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21
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Ahmed SA, Parama D, Daimari E, Girisa S, Banik K, Harsha C, Dutta U, Kunnumakkara AB. Rationalizing the therapeutic potential of apigenin against cancer. Life Sci 2020; 267:118814. [PMID: 33333052 DOI: 10.1016/j.lfs.2020.118814] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/14/2020] [Accepted: 11/20/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Despite the remarkable advances made in the diagnosis and treatment of cancer during the past couple of decades, it remains the second largest cause of mortality in the world, killing approximately 9.6 million people annually. The major challenges in the treatment of the advanced stage of this disease are the development of chemoresistance, severe adverse effects of the drugs, and high treatment cost. Therefore, the development of drugs that are safe, efficacious, and cost-effective remains a 'Holy Grail' in cancer research. However, the research over the past four decades shed light on the cancer-preventive and therapeutic potential of natural products and their underlying mechanism of action. Apigenin is one such compound, which is known to be safe and has significant potential in the prevention and therapy of this disease. AIM To assess the literature available on the potential of apigenin and its analogs in modulating the key molecular targets leading to the prevention and treatment of different types of cancer. METHOD A comprehensive literature search has been carried out on PubMed for obtaining information related to the sources and analogs, chemistry and biosynthesis, physicochemical properties, biological activities, bioavailability and toxicity of apigenin. KEY FINDINGS The literature search resulted in many in vitro, in vivo and a few cohort studies that evidenced the effectiveness of apigenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK/ERK, Wnt/β-catenin, etc., which play a crucial role in the development and progression of cancer. In addition, apigenin was also shown to inhibit chemoresistance and radioresistance and make cancer cells sensitive to these agents. Reports have further revealed the safety of the compound and the adaptation of nanotechnological approaches for improving its bioavailability. SIGNIFICANCE Hence, the present review recapitulates the properties of apigenin and its pharmacological activities against different types of cancer, which warrant further investigation in clinical settings.
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Affiliation(s)
- Semim Akhtar Ahmed
- Cell and Molecular Biology Laboratory, Department of Zoology, Cotton University, Pan Bazar, Guwahati, Assam 781001, India
| | - Dey Parama
- Cancer Biology Laboratory and DBT-AIST International Center for Translational and Environmental Research (DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Enush Daimari
- Cell and Molecular Biology Laboratory, Department of Zoology, Cotton University, Pan Bazar, Guwahati, Assam 781001, India
| | - Sosmitha Girisa
- Cancer Biology Laboratory and DBT-AIST International Center for Translational and Environmental Research (DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Kishore Banik
- Cancer Biology Laboratory and DBT-AIST International Center for Translational and Environmental Research (DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Choudhary Harsha
- Cancer Biology Laboratory and DBT-AIST International Center for Translational and Environmental Research (DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Uma Dutta
- Cell and Molecular Biology Laboratory, Department of Zoology, Cotton University, Pan Bazar, Guwahati, Assam 781001, India.
| | - Ajaikumar B Kunnumakkara
- Cancer Biology Laboratory and DBT-AIST International Center for Translational and Environmental Research (DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India.
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22
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Morgan D, Garg M, Tergaonkar V, Tan SY, Sethi G. Pharmacological significance of the non-canonical NF-κB pathway in tumorigenesis. Biochim Biophys Acta Rev Cancer 2020; 1874:188449. [PMID: 33058996 DOI: 10.1016/j.bbcan.2020.188449] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/04/2020] [Accepted: 10/05/2020] [Indexed: 02/06/2023]
Abstract
The understanding of the impact of the non-canonical NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathway in several human diseases including autoimmune, inflammatory and cancers has been on the rise. This pathway induces the expression of several important genes involved in diverse biological processes. Though progress has been made in understanding the activation, regulation and biological functions of the non-canonical NF-κB signaling mechanism, no specific drug has been approved to target NF-κB inducing kinase (NIK), the key signaling molecule in this pathway. The inhibition of NIK can serve as a potential therapeutic strategy for various ailments, especially for the treatment of different types of human cancers. There are other targetable downstream molecules in this pathway as well. This review highlights the possible role of the non-canonical NF-κB pathway in normal physiology as well as in different cancers and discusses about various pharmacological strategies to modulate the activation of this pathway.
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Affiliation(s)
- Dhakshayini Morgan
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673, Singapore; Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Lower Kent Ridge Road, 119 074, Singapore
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University, Uttar Pradesh, Noida 201313, India
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673, Singapore; Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Lower Kent Ridge Road, 119 074, Singapore; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore.
| | - Soo Yong Tan
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Lower Kent Ridge Road, 119 074, Singapore; Advanced Molecular Pathology Laboratory, Institute of Molecular and Cell Biology, 61 Biopolis Dr, 138673, Singapore
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117 600, Singapore.
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23
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Chen Y, Ho L, Tergaonkar V. sORF-Encoded MicroPeptides: New players in inflammation, metabolism, and precision medicine. Cancer Lett 2020; 500:263-270. [PMID: 33157158 DOI: 10.1016/j.canlet.2020.10.038] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/16/2020] [Accepted: 10/21/2020] [Indexed: 12/30/2022]
Abstract
Significant technological advances have enabled the discovery and identification of a new class of molecules, micropeptides or small ORF encoded peptides (SEPs) within non-coding RNAs (ncRNAs). As ncRNAs are well known to be transcriptionally silent, the discovery of SEPs implies that many ncRNAs are misannotated or play both coding and non-coding functions. SEPs have reportedly diverse regulatory roles in embryogenesis, myogenesis, inflammation, diseases, and cancer. SEPs appearing in different subcellular compartments show distinct functions. In this review, we summarized the functions of SEPs that have been characterized thus far. As SEPs are amenable to therapeutic development as biologics, understanding their underlying functions will provide novel targets for the treatment of inflammatory or metabolic disorders.
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Affiliation(s)
- Ying Chen
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, 138673, Singapore.
| | - Lena Ho
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, 138673, Singapore; Cardiovascular Metabolic Disorders Program, Duke-NUS Graduate School, Singapore; Institute of Medical Biology, A*STAR, Singapore
| | - Vinay Tergaonkar
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, 138673, Singapore; Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore, 117597, Singapore.
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24
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Kirtonia A, Sethi G, Garg M. The multifaceted role of reactive oxygen species in tumorigenesis. Cell Mol Life Sci 2020; 77:4459-4483. [PMID: 32358622 PMCID: PMC11105050 DOI: 10.1007/s00018-020-03536-5] [Citation(s) in RCA: 241] [Impact Index Per Article: 60.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/29/2020] [Accepted: 04/20/2020] [Indexed: 02/06/2023]
Abstract
Redox homeostasis is an essential requirement of the biological systems for performing various normal cellular functions including cellular growth, differentiation, senescence, survival and aging in humans. The changes in the basal levels of reactive oxygen species (ROS) are detrimental to cells and often lead to several disease conditions including cardiovascular, neurological, diabetes and cancer. During the last two decades, substantial research has been done which clearly suggests that ROS are essential for the initiation, progression, angiogenesis as well as metastasis of cancer in several ways. During the last two decades, the potential of dysregulated ROS to enhance tumor formation through the activation of various oncogenic signaling pathways, DNA mutations, immune escape, tumor microenvironment, metastasis, angiogenesis and extension of telomere has been discovered. At present, surgery followed by chemotherapy and/or radiotherapy is the major therapeutic modality for treating patients with either early or advanced stages of cancer. However, the majority of patients relapse or did not respond to initial treatment. One of the reasons for recurrence/relapse is the altered levels of ROS in tumor cells as well as in cancer-initiating stem cells. One of the critical issues is targeting the intracellular/extracellular ROS for significant antitumor response and relapse-free survival. Indeed, a large number of FDA-approved anticancer drugs are efficient to eliminate cancer cells and drug resistance by increasing ROS production. Thus, the modulation of oxidative stress response might represent a potential approach to eradicate cancer in combination with FDA-approved chemotherapies, radiotherapies as well as immunotherapies.
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Affiliation(s)
- Anuradha Kirtonia
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Campus, Sector-125, Noida, Uttar Pradesh, 201313, India
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore.
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Campus, Sector-125, Noida, Uttar Pradesh, 201313, India.
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25
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Koebner phenomenon leading to the formation of new psoriatic lesions: evidences and mechanisms. Biosci Rep 2020; 39:221063. [PMID: 31710084 PMCID: PMC6893164 DOI: 10.1042/bsr20193266] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 12/16/2022] Open
Abstract
Koebner phenomenon refers to the emergence of new psoriatic lesions in the healthy skin regions following an injury/trauma to psoriatic patients. The occurrence of psoriatic lesions at unusual areas of the body regions such as on penis, around eyes and on keloids suggest that the Koebner phenomenon may be responsible for these lesions. A number of agents/triggers have been reported to induce the development of new psoriatic lesions in healthy skin areas and these include, tattooing skin, radiations, skin incision, viral infections and striae etc. The different mechanisms that contribute in inducing the development of new psoriatic lesions as Koebernization include the involvement of mast cell-derived inflammatory mediators such as tryptase, IL-6, IL-8, IL-17, and IL-36γ. Moreover, an increased expression of nerve growth factor (NGF) and vascular endothelial growth factor (VEGF) also contribute in Koebernization. Apart from these, there is a critical role of α 2 β1 integrins, S100A7 (psoriasin) and S100A15 (koebnerisin), change in the ratio of CD4+/CD8+ T cells, down-regulation of mechanosensitive polycystin 1 protein, decrease in inflammation controlling atypical chemokine receptor 2 (ACKR2), reduced expression of N-methyl-d-aspartate (NMDA) receptors (NMDARs) on the keratinocytes and increase in levels of chemokines (CXCL8 and CCL20) in inducing formation of new psoriatic lesions. The present review discusses the role of Koebner phenomenon in the development of new psoriatic lesions. Moreover, it also describes the mechanisms involved in Koebernization in the form of discussion of different key targets that may be potentially modulated pharmacologically to attenuate/halt the development of new psoriatic lesions.
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Engineering anti-cancer nanovaccine based on antigen cross-presentation. Biosci Rep 2020; 39:220729. [PMID: 31652460 PMCID: PMC6822533 DOI: 10.1042/bsr20193220] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/27/2019] [Accepted: 10/01/2019] [Indexed: 01/16/2023] Open
Abstract
Dendritic cells (DCs) present exogenous antigens on major histocompatibility complex (MHC) class I molecules, thereby activating CD8+ T cells, contributing to tumor elimination through a mechanism known as antigen cross-presentation. A variety of factors such as maturation state of DCs, co-stimulatory signals, T-cell microenvironment, antigen internalization routes and adjuvants regulate the process of DC-mediated antigen cross-presentation. Recently, the development of successful cancer immunotherapies may be attributed to the ability of DCs to cross-present tumor antigens. In this review article, we focus on the underlying mechanism of antigen cross-presentation and ways to improve antigen cross-presentation in different DC subsets. We have critically summarized the recent developments in the generation of novel nanovaccines for robust CD8+ T-cell response in cancer. In this context, we have reviewed nanocarriers that have been used for cancer immunotherapeutics based on antigen cross-presentation mechanism. Additionally, we have also expressed our views on the future applications of this mechanism in curing cancer.
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27
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Wong AHH, Shin EM, Tergaonkar V, Chng WJ. Targeting NF-κB Signaling for Multiple Myeloma. Cancers (Basel) 2020; 12:cancers12082203. [PMID: 32781681 PMCID: PMC7463546 DOI: 10.3390/cancers12082203] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 07/30/2020] [Accepted: 08/01/2020] [Indexed: 12/11/2022] Open
Abstract
Multiple myeloma (MM) is the second most common hematologic malignancy in the world. Even though survival rates have significantly risen over the past years, MM remains incurable, and is also far from reaching the point of being managed as a chronic disease. This paper reviews the evolution of MM therapies, focusing on anti-MM drugs that target the molecular mechanisms of nuclear factor kappa B (NF-κB) signaling. We also provide our perspectives on contemporary research findings and insights for future drug development.
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Affiliation(s)
- Ada Hang-Heng Wong
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore; (E.M.S.); (V.T.)
- AW Medical Company Limited, Macau, China
- Correspondence: (A.H.-H.W.); (W.-J.C.); Tel.: +65-6586-9709 (A.H.-H.W.); +65-6772-4612 (W.-J.C.)
| | - Eun Myoung Shin
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore; (E.M.S.); (V.T.)
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore; (E.M.S.); (V.T.)
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119074, Singapore
- Department of Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA 5000, Australia
| | - Wee-Joo Chng
- Cancer Science Institute of Singapore, Singapore 117599, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
- Department of Hematology-Oncology, National University Cancer Institute of Singapore, National University Health System, Singapore 119074, Singapore
- Correspondence: (A.H.-H.W.); (W.-J.C.); Tel.: +65-6586-9709 (A.H.-H.W.); +65-6772-4612 (W.-J.C.)
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28
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The TERT copy number gain is sensitive to telomerase inhibitors in human melanoma. Clin Sci (Lond) 2020; 134:193-205. [PMID: 31919521 DOI: 10.1042/cs20190890] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/03/2020] [Accepted: 01/09/2020] [Indexed: 12/11/2022]
Abstract
Telomerase reverse transcriptase (TERT) copy number gain is frequently observed in Asian melanoma patients. Here, we explored the correlation between TERT copy number and the effect of telomerase inhibitors in melanoma. A total of 78 melanoma cases were enrolled in the study. The TERT copy number was examined by QuantiGene Plex DNA assay. The sensitivity to telomerase inhibitors was evaluated in cell lines and patient-derived xenograft (PDX) models with or without TERT copy number gain. Among the 78 patients, 33.3% showed TERT copy number gain, and the incidence of this gain in acral melanoma (61.5%) was higher than that in other melanoma subtypes (P=0.02). The telomerase inhibitors 6-thio-2'-deoxyguanosine (6-Thio-dG) and epigallocatechin-3-gallate (EGCG) inhibited cell viability and repressed tumor growth in PDX models with TERT copy number gain. TERT copy number gain is frequently observed in Chinese patients with melanoma. Targeting telomerase may benefit melanoma patients with TERT copy number gain.
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29
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Fernandes SG, Dsouza R, Pandya G, Kirtonia A, Tergaonkar V, Lee SY, Garg M, Khattar E. Role of Telomeres and Telomeric Proteins in Human Malignancies and Their Therapeutic Potential. Cancers (Basel) 2020; 12:E1901. [PMID: 32674474 PMCID: PMC7409176 DOI: 10.3390/cancers12071901] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/19/2022] Open
Abstract
Telomeres are the ends of linear chromosomes comprised of repetitive nucleotide sequences in humans. Telomeres preserve chromosomal stability and genomic integrity. Telomere length shortens with every cell division in somatic cells, eventually resulting in replicative senescence once telomere length becomes critically short. Telomere shortening can be overcome by telomerase enzyme activity that is undetectable in somatic cells, while being active in germline cells, stem cells, and immune cells. Telomeres are bound by a shelterin complex that regulates telomere lengthening as well as protects them from being identified as DNA damage sites. Telomeres are transcribed by RNA polymerase II, and generate a long noncoding RNA called telomeric repeat-containing RNA (TERRA), which plays a key role in regulating subtelomeric gene expression. Replicative immortality and genome instability are hallmarks of cancer and to attain them cancer cells exploit telomere maintenance and telomere protection mechanisms. Thus, understanding the role of telomeres and their associated proteins in cancer initiation, progression and treatment is very important. The present review highlights the critical role of various telomeric components with recently established functions in cancer. Further, current strategies to target various telomeric components including human telomerase reverse transcriptase (hTERT) as a therapeutic approach in human malignancies are discussed.
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Affiliation(s)
- Stina George Fernandes
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
| | - Rebecca Dsouza
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
| | - Gouri Pandya
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Anuradha Kirtonia
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; (V.T.); (S.Y.L.)
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore
| | - Sook Y. Lee
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; (V.T.); (S.Y.L.)
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Ekta Khattar
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
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30
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Xie T, Fan Z, Zhang R, Tian X, Han G, Liu Z, Zhang Z. In situ imaging of intracellular human telomerase RNA with molecular beacon-functionalized gold nanoparticles. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:2385-2390. [PMID: 32930264 DOI: 10.1039/d0ay00461h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Since the expression level of human telomerase RNA (hTR) in tumor cells is much higher than that in normal cells, the determination of hTR is of prime importance in biological research of tumors. In this work, we report molecular beacon-functionalized gold nanoparticles for hTR imaging in live cells. The molecular beacon has a loop-and-stem structure with hTR recognition sequences and a red fluorophore Cy5. In the presence of hTR, the hTR sequence could be hybridized with the loop of molecular beacon to form a duplex DNA chain and thus the fluorescence state switched from "off" to "on". After co-incubation with cells, the probe could readily permeate into cells, leading to the in situ imaging of intracellular hTR. The proposed approach could be used to differentiate tumor cells from normal ones and assess hTR expression levels in different tumor cells. Furthermore, the proposed approach allowed us to dynamically monitor the expression level of hTR in live cells and holds great potential for application in tumor diagnosis and hTR-related drug delivery.
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Affiliation(s)
- Tao Xie
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Ziyan Fan
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Ruilong Zhang
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Xiaohe Tian
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Guangmei Han
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Zhengjie Liu
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
| | - Zhongping Zhang
- Institute of Physical Science and Information Technology, School of Chemical and Chemical Engineering, School of Life Science, Anhui University, Hefei, Anhui 230601, China.
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Lam H, Tergaonkar V, Ahn K. Mechanisms of allergen-specific immunotherapy for allergic rhinitis and food allergies. Biosci Rep 2020; 40:BSR20200256. [PMID: 32186703 PMCID: PMC7109000 DOI: 10.1042/bsr20200256] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/15/2022] Open
Abstract
Allergen-specific immunotherapy (AIT) is currently the only potential treatment for allergies including allergic rhinitis (AR) and food allergies (FA) that can modify the underlying course of the diseases. Although AIT has been performed for over a century, the precise and detailed mechanism for AIT is still unclear. Previous clinical trials have reported that successful AIT induces the reinstatement of tolerance against the specific allergen. In this review, we aim to provide an updated summary of the knowledge on the underlying mechanisms of IgE-mediated AR and FA as well as the immunological changes observed after AIT and discuss on how better understanding of these can lead to possible identification of biomarkers and novel strategies for AIT.
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Affiliation(s)
- Hiu Yan Lam
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117596, Singapore
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117596, Singapore
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117596, Singapore
| | - Kwang Seok Ahn
- Department of Science in Korean Medicine, Kyung Hee University, 24 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea
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32
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Expression of telomerase reverse transcriptase positively correlates with duration of lithium treatment in bipolar disorder. Psychiatry Res 2020; 286:112865. [PMID: 32114208 PMCID: PMC7334059 DOI: 10.1016/j.psychres.2020.112865] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/07/2020] [Accepted: 02/11/2020] [Indexed: 01/05/2023]
Abstract
Bipolar disorder (BD) may be associated with accelerated cellular aging. However, previous studies on telomere length (TL), an important biomarker of cellular aging, have yielded mixed results in BD. We aimed to evaluate the hypothesis that BD is associated with telomere shortening and whether this is counteracted by long-term lithium treatment. We also sought to determine whether long-term lithium treatment is associated with increased expression of telomerase reverse transcriptase (TERT), the catalytic subunit of telomerase. We determined TL and TERT expression in 100 BD I patients and 100 healthy controls. We also genotyped three single nucleotide polymorphisms associated with TL. TERT expression was significantly increased in BD I patients currently on lithium treatment. TERT expression was also significantly positively correlated with duration of lithium treatment in patients treated for 24 months or more. However, we did not find any significant effect of lithium treatment on TL. Neither did we find significant differences in TL between BD patients and controls. We suggest that long-term lithium treatment is associated with an increase in the expression of TERT. We hypothesize that an increase in TERT expression may contribute to lithium's mood stabilizing and neuroprotective properties by improving mitochondrial function and decreasing oxidative stress.
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33
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The Solo Play of TERT Promoter Mutations. Cells 2020; 9:cells9030749. [PMID: 32204305 PMCID: PMC7140675 DOI: 10.3390/cells9030749] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/16/2020] [Accepted: 03/16/2020] [Indexed: 12/13/2022] Open
Abstract
The reactivation of telomerase reverse transcriptase (TERT) protein is the principal mechanism of telomere maintenance in cancer cells. Mutations in the TERT promoter (TERTp) are a common mechanism of TERT reactivation in many solid cancers, particularly those originating from slow-replicating tissues. They are associated with increased TERT levels, telomere stabilization, and cell immortalization and proliferation. Much effort has been invested in recent years in characterizing their prevalence in different cancers and their potential as biomarkers for tumor stratification, as well as assessing their molecular mechanism of action, but much remains to be understood. Notably, they appear late in cell transformation and are mutually exclusive with each other as well as with other telomere maintenance mechanisms, indicative of overlapping selective advantages and of a strict regulation of TERT expression levels. In this review, we summarized the latest literature on the role and prevalence of TERTp mutations across different cancer types, highlighting their biased distribution. We then discussed the need to maintain TERT levels at sufficient levels to immortalize cells and promote proliferation while remaining within cell sustainability levels. A better understanding of TERT regulation is crucial when considering its use as a possible target in antitumor strategies.
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34
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Wu L, Fidan K, Um JY, Ahn KS. Telomerase: Key regulator of inflammation and cancer. Pharmacol Res 2020; 155:104726. [PMID: 32109579 DOI: 10.1016/j.phrs.2020.104726] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 02/24/2020] [Accepted: 02/24/2020] [Indexed: 12/11/2022]
Abstract
The telomerase holoenzyme, which has a highly conserved role in maintaining telomere length, has long been regarded as a high-profile target in cancer therapy due to the high dependency of the majority of cancer cells on constitutive and elevated telomerase activity for sustained proliferation and immortality. In this review, we present the salient findings in the telomerase field with special focus on the association of telomerase with inflammation and cancer. The elucidation of extra-telomeric roles of telomerase in inflammation, reactive oxygen species (ROS) generation, and cancer development further complicated the design of anti-telomerase therapy. Of note, the discovery of the unique mechanism that underlies reactivation of the dormant telomerase reverse transcriptase TERT promoter in somatic cells not only enhanced our understanding of the critical role of TERT in carcinogenesis but also opens up new intervention ideas that enable the differential targeting of cancer cells only. Despite significant effort invested in developing telomerase-targeted therapeutics, devising efficacious cancer-specific telomerase/TERT inhibitors remains an uphill task. The latest discoveries of the telomere-independent functionalities of telomerase in inflammation and cancer can help illuminate the path of developing specific anti-telomerase/TERT therapeutics against cancer cells.
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Affiliation(s)
- Lele Wu
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore
| | - Kerem Fidan
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore
| | - Jae-Young Um
- College of Korean Medicine, Kyung Hee University, #47, Kyungheedae-gil, Dongdaemoon-gu, Seoul 130-701, Republic of Korea
| | - Kwang Seok Ahn
- College of Korean Medicine, Kyung Hee University, #47, Kyungheedae-gil, Dongdaemoon-gu, Seoul 130-701, Republic of Korea.
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35
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Khattar E, Maung KZY, Chew CL, Ghosh A, Mok MMH, Lee P, Zhang J, Chor WHJ, Cildir G, Wang CQ, Mohd-Ismail NK, Chin DWL, Lee SC, Yang H, Shin YJ, Nam DH, Chen L, Kumar AP, Deng LW, Ikawa M, Gunaratne J, Osato M, Tergaonkar V. Rap1 regulates hematopoietic stem cell survival and affects oncogenesis and response to chemotherapy. Nat Commun 2019; 10:5349. [PMID: 31836706 PMCID: PMC6911077 DOI: 10.1038/s41467-019-13082-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/14/2019] [Indexed: 11/09/2022] Open
Abstract
Increased levels and non-telomeric roles have been reported for shelterin proteins, including RAP1 in cancers. Herein using Rap1 null mice, we provide the genetic evidence that mammalian Rap1 plays a major role in hematopoietic stem cell survival, oncogenesis and response to chemotherapy. Strikingly, this function of RAP1 is independent of its association with the telomere or with its known partner TRF2. We show that RAP1 interacts with many members of the DNA damage response (DDR) pathway. RAP1 depleted cells show reduced interaction between XRCC4/DNA Ligase IV and DNA-PK, and are impaired in DNA Ligase IV recruitment to damaged chromatin for efficient repair. Consistent with its role in DNA damage repair, RAP1 loss decreases double-strand break repair via NHEJ in vivo, and consequently reduces B cell class switch recombination. Finally, we discover that RAP1 levels are predictive of the success of chemotherapy in breast and colon cancer.
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Affiliation(s)
- Ekta Khattar
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Kyaw Ze Ya Maung
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Chen Li Chew
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Arkasubhra Ghosh
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Michelle Meng Huang Mok
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Pei Lee
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Jun Zhang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Science, Nanjing Normal University, 210023, Nanjing, P.R. China
| | - Wei Hong Jeff Chor
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Gökhan Cildir
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Chelsia Qiuxia Wang
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Nur Khairiah Mohd-Ismail
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Desmond Wai Loon Chin
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Soo Chin Lee
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Henry Yang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Yong-Jae Shin
- Institute for Refractory Cancer Research, Samsung Medical Center, Seoul, Republic of Korea
| | - Do-Hyun Nam
- Institute for Refractory Cancer Research, Samsung Medical Center, Seoul, Republic of Korea
| | - Liming Chen
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Science, Nanjing Normal University, 210023, Nanjing, P.R. China
| | - Alan Prem Kumar
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Lih Wen Deng
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Masahito Ikawa
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, 565-0871, Japan
- Graduate School of Medicine, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Jayantha Gunaratne
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Motomi Osato
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Vinay Tergaonkar
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A-STAR), Singapore, Singapore.
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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Perera ON, Sobinoff AP, Teber ET, Harman A, Maritz MF, Yang SF, Pickett HA, Cesare AJ, Arthur JW, MacKenzie KL, Bryan TM. Telomerase promotes formation of a telomere protective complex in cancer cells. SCIENCE ADVANCES 2019; 5:eaav4409. [PMID: 31616780 PMCID: PMC6774720 DOI: 10.1126/sciadv.aav4409] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 09/09/2019] [Indexed: 05/04/2023]
Abstract
Telomerase is a ribonucleoprotein complex that catalyzes addition of telomeric DNA repeats to maintain telomeres in replicating cells. Here, we demonstrate that the telomerase protein hTERT performs an additional role at telomeres that is independent of telomerase catalytic activity yet essential for telomere integrity and cell proliferation. Short-term depletion of endogenous hTERT reduced the levels of heat shock protein 70 (Hsp70-1) and the telomere protective protein Apollo at telomeres, and induced telomere deprotection and cell cycle arrest, in the absence of telomere shortening. Short-term expression of hTERT promoted colocalization of Hsp70-1 with telomeres and Apollo and reduced numbers of deprotected telomeres, in a manner independent of telomerase catalytic activity. These data reveal a previously unidentified noncanonical function of hTERT that promotes formation of a telomere protective complex containing Hsp70-1 and Apollo and is essential for sustained proliferation of telomerase-positive cancer cells, likely contributing to the known cancer-promoting effects of both hTERT and Hsp70-1.
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Affiliation(s)
- Omesha N. Perera
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Alexander P. Sobinoff
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Erdahl T. Teber
- Bioinformatics Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Ashley Harman
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Michelle F. Maritz
- Children’s Cancer Institute, School of Women’s and Children’s Health, University of NSW, NSW 2052, Australia
| | - Sile F. Yang
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Hilda A. Pickett
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Anthony J. Cesare
- Genome Integrity Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Jonathan W. Arthur
- Bioinformatics Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Karen L. MacKenzie
- Children’s Cancer Institute, School of Women’s and Children’s Health, University of NSW, NSW 2052, Australia
| | - Tracy M. Bryan
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
- Corresponding author.
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Ginkgetin attenuates cerebral ischemia-reperfusion induced autophagy and cell death via modulation of the NF-κB/p53 signaling pathway. Biosci Rep 2019; 39:BSR20191452. [PMID: 31420372 PMCID: PMC6732367 DOI: 10.1042/bsr20191452] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/27/2019] [Accepted: 08/01/2019] [Indexed: 12/12/2022] Open
Abstract
Background: Cerebral ischemia–reperfusion (I/R) injury is the key to fatality in cerebrovascular accident, hence further endeavor is warranted to delineate the mechanism underlying its lethal aggravation procedure. In the present study, we aimed to elucidate the anti-autophagy and anti-apoptosis effects of ginkgetin via nuclear factor κB (NF-κB)/p53 pathway in cerebral I/R rats. Methods: Rats were administrated 2-h occlusion of right middle cerebral artery before the 24-h reperfusion followed. There were three doses of ginkgetin (25, 50, 100 mg/kg) given intraperitoneally (i.p.) after the 2-h ischemia, and Pifithrin-α (PFT-α, p53 inhibitor), SN50 (NF-κB inhibitor) and 3-methyladenine (3-MA, autophagy inhibitor) was administered 20 min before the ischemia, respectively. Results: The neurological deficits decreased significantly with the administration of ginkgetin. The concentrations of microtubule-associated protein 1 light chain 3-II and p53 were significantly decreased by PFT-α, 3-MA and ginkgetin. The concentrations of Beclin 1, damage-regulated autophagy modulator, cathepsin B and cathepsin D were significantly decreased due to the administration of PFT-α, ginkgetin and SN50. Furthermore, the concentrations of Bax and p53-upregulated modulator of apoptosis were significantly decreased with that of Bcl-2 being significantly increased by administration of SN50, PFT-α and ginkgetin. Conclusion: Ginkgetin can alleviate cerebral ischemia/reperfusion induced autophagy and apoptosis by inhibiting the NF-κB/p53 signaling pathway.
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Roy NK, Parama D, Banik K, Bordoloi D, Devi AK, Thakur KK, Padmavathi G, Shakibaei M, Fan L, Sethi G, Kunnumakkara AB. An Update on Pharmacological Potential of Boswellic Acids against Chronic Diseases. Int J Mol Sci 2019; 20:ijms20174101. [PMID: 31443458 PMCID: PMC6747466 DOI: 10.3390/ijms20174101] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/16/2019] [Accepted: 08/16/2019] [Indexed: 02/07/2023] Open
Abstract
Natural compounds, in recent years, have attracted significant attention for their use in the prevention and treatment of diverse chronic diseases as they are devoid of major toxicities. Boswellic acid (BA), a series of pentacyclic triterpene molecules, is isolated from the gum resin of Boswellia serrata and Boswellia carteri. It proved to be one such agent that has exhibited efficacy against various chronic diseases like arthritis, diabetes, asthma, cancer, inflammatory bowel disease, Parkinson’s disease, Alzheimer’s, etc. The molecular targets attributed to its wide range of biological activities include transcription factors, kinases, enzymes, receptors, growth factors, etc. The present review is an attempt to demonstrate the diverse pharmacological uses of BA, along with its underlying molecular mechanism of action against different ailments. Further, this review also discusses the roadblocks associated with the pharmacokinetics and bioavailability of this promising compound and strategies to overcome those limitations for developing it as an effective drug for the clinical management of chronic diseases.
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Affiliation(s)
- Nand Kishor Roy
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Dey Parama
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Kishore Banik
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Devivasha Bordoloi
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Amrita Khwairakpam Devi
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Krishan Kumar Thakur
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Ganesan Padmavathi
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Mehdi Shakibaei
- Musculoskeletal Research Group and Tumour Biology, Chair of Vegetative Anatomy, Institute of Anatomy, Ludwig-Maximilian-University, 80336 Munich, Germany
| | - Lu Fan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore.
| | - Ajaikumar B Kunnumakkara
- Cancer Biology Laboratory and DBT-AIST International Centre for Translational and Environmental Research(DAICENTER), Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam 781039, India.
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Ohira T, Kojima H, Kuroda Y, Aoki S, Inaoka D, Osaki M, Wanibuchi H, Okada F, Oshimura M, Kugoh H. PITX1 protein interacts with ZCCHC10 to regulate hTERT mRNA transcription. PLoS One 2019; 14:e0217605. [PMID: 31404068 PMCID: PMC6690549 DOI: 10.1371/journal.pone.0217605] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/29/2019] [Indexed: 01/21/2023] Open
Abstract
Telomerase is a ribonucleoprotein ribonucleic enzyme that is essential for cellular immortalization via elongation of telomere repeat sequences at the end of chromosomes. Human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase holoenzyme, is a key regulator of telomerase activity. Telomerase activity, which has been detected in the majority of cancer cells, is accompanied by hTERT expression, suggesting that this enzyme activity contributes to an unlimited replication potential of cancer cells via regulation of telomere length. Thus, hTERT is an attractive target for cancer-specific treatments. We previously reported that pared-like homeodomain 1 (PITX1) is a negative regulator of hTERT through direct binding to the hTERT promoter. However, the mechanism by which the function of PITX1 contributes to transcriptional silencing of the hTERT gene remains to be clarified. Here, we show that PITX1 and zinc finger CCHC-type containing 10 (ZCCHC10) proteins cooperate to facilitate the transcriptional regulation of the hTERT gene by functional studies via FLAG pull-down assay. Co-expression of PITX1 and ZCCHC10 resulted in inhibition of hTERT transcription, in melanoma cell lines, whereas mutate-deletion of homeodomain in PITX1 that interact with ZCCHC10 did not induce similar phenotypes. In addition, ZCCHC10 expression levels showed marked decrease in the majority of melanoma cell lines and tissues. Taken together, these results suggest that ZCCHC10-PITX1 complex is the functional unit that suppresses hTERT transcription, and may play a crucial role as a novel tumor suppressor complex.
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Affiliation(s)
- Takahito Ohira
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
| | - Hirotada Kojima
- Department of Immunology, Graduate School of Medicine, Osaka City University, Asahi-machi, Abeno-ku, Osaka, Japan
| | - Yuko Kuroda
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
| | - Sayaka Aoki
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
| | - Daigo Inaoka
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
| | - Mitsuhiko Osaki
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
- Division of Pathological Biochemistry, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Hideki Wanibuchi
- Department of Molecular Pathology, Graduate School of Medicine, Osaka City University, Asahi-machi, Abeno-ku, Osaka, Japan
| | - Futoshi Okada
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
- Division of Pathological Biochemistry, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Mitsuo Oshimura
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
| | - Hiroyuki Kugoh
- Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
- Chromosome Engineering Research Center, Tottori University, Yonago, Tottori, Japan
- * E-mail:
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FEZF1-AS1: a novel vital oncogenic lncRNA in multiple human malignancies. Biosci Rep 2019; 39:BSR20191202. [PMID: 31175144 PMCID: PMC6591563 DOI: 10.1042/bsr20191202] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 12/24/2022] Open
Abstract
Long noncoding RNAs (LncRNAs) refer to the RNA with a length of >200 nucleotides, which lack or have no open reading coding frame and have higher tissue and organ specificity compared with the protein coding genes. A surging number of studies have shown that lncRNA is involved in numerous essential regulatory processes, such as X chromosome silencing, genomic imprinting, chromatin modification, transcriptional activation, transcriptional interference and nuclear transport, which are closely related to the occurrence and development of human malignancies. FEZ family Zinc Finger 1-Antisense RNA 1 (FEZF1-AS1) of FEZ family is a recently discovered lncRNA. FEZF1-AS1 is highly expressed in pancreatic cancer, colorectal cancer, lung adenocarcinoma and other human malignancies, and is associated with poor prognosis. As an oncogene, it plays crucial role in the proliferation, migration, invasion and Warburg effect of various tumor cells. In addition, FEZF1-AS1 is also involved in the regulation of multiple signal pathways such as epithelial–mesenchymal transition (EMT), signal transducer and activator of transcription 3 (STAT3) and Wnt/ β-catenin. In this paper, the recent research progress of FEZF1-AS1 in tumorigenesis and development is reviewed systematically.
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Insights into Telomerase/hTERT Alternative Splicing Regulation Using Bioinformatics and Network Analysis in Cancer. Cancers (Basel) 2019; 11:cancers11050666. [PMID: 31091669 PMCID: PMC6562651 DOI: 10.3390/cancers11050666] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 01/08/2023] Open
Abstract
The reactivation of telomerase in cancer cells remains incompletely understood. The catalytic component of telomerase, hTERT, is thought to be the limiting component in cancer cells for the formation of active enzymes. hTERT gene expression is regulated at several levels including chromatin, DNA methylation, transcription factors, and RNA processing events. Of these regulatory events, RNA processing has received little attention until recently. RNA processing and alternative splicing regulation have been explored to understand how hTERT is regulated in cancer cells. The cis- and trans-acting factors that regulate the alternative splicing choice of hTERT in the reverse transcriptase domain have been investigated. Further, it was discovered that the splicing factors that promote the production of full-length hTERT were also involved in cancer cell growth and survival. The goals are to review telomerase regulation via alternative splicing and the function of hTERT splicing variants and to point out how bioinformatics approaches are leading the way in elucidating the networks that regulate hTERT splicing choice and ultimately cancer growth.
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Focus on Formononetin: Anticancer Potential and Molecular Targets. Cancers (Basel) 2019; 11:cancers11050611. [PMID: 31052435 PMCID: PMC6562434 DOI: 10.3390/cancers11050611] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/22/2019] [Accepted: 04/28/2019] [Indexed: 12/11/2022] Open
Abstract
Formononetin, an isoflavone, is extracted from various medicinal plants and herbs, including the red clover (Trifolium pratense) and Chinese medicinal plant Astragalus membranaceus. Formononetin's antioxidant and neuroprotective effects underscore its therapeutic use against Alzheimer's disease. Formononetin has been under intense investigation for the past decade as strong evidence on promoting apoptosis and against proliferation suggests for its use as an anticancer agent against diverse cancers. These anticancer properties are observed in multiple cancer cell models, including breast, colorectal, and prostate cancer. Formononetin also attenuates metastasis and tumor growth in various in vivo studies. The beneficial effects exuded by formononetin can be attributed to its antiproliferative and cell cycle arrest inducing properties. Formononetin regulates various transcription factors and growth-factor-mediated oncogenic pathways, consequently alleviating the possible causes of chronic inflammation that are linked to cancer survival of neoplastic cells and their resistance against chemotherapy. As such, this review summarizes and critically analyzes current evidence on the potential of formononetin for therapy of various malignancies with special emphasis on molecular targets.
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LncRNA CASC11 promotes cancer cell proliferation in hepatocellular carcinoma by inhibiting miRNA-188-5p. Biosci Rep 2019; 39:BSR20190251. [PMID: 30910841 PMCID: PMC6488862 DOI: 10.1042/bsr20190251] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/07/2019] [Accepted: 03/08/2019] [Indexed: 12/12/2022] Open
Abstract
It is known that lncRNA CASC11 promotes the development of gastric cancer. Our study was carried out to investigate the possible involvement of ncRNA CASC11 in hepatocellular carcinoma (HCC). In the present study, we found that CASC11 was up-regulated, while miR-188-5p was down-regulated in tumor tissues of HCC patients. CASC11 and miR-188-5p were not affected by HBV and HCV infections. Follow-up study showed that high levels of CASC11 were significantly correlated with poor survival. Expression levels of CASC11 and miR-188-5p were inversely correlated in tumor tissues. CASC11 overexpression mediated the down-regulation of miR-188-5p, while miR-188-5p overexpression failed to affect CASC11 expression. CASC11 overexpression led to promoted, while miR-188-5p overexpression led to inhibited proliferation of cells of HCC cell lines. CASC11 overexpression showed no significant effects on cancer cell migration and invasion. In addition, miR-188-5p overexpression attenuated the enhancing effects of CASC11 overexpression on cancer cell proliferation. Therefore, LncRNA CASC11 promoted cancer cell proliferation in HCC possibly by inhibiting miR-188-5p.
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NOD-like receptors: major players (and targets) in the interface between innate immunity and cancer. Biosci Rep 2019; 39:BSR20181709. [PMID: 30837326 PMCID: PMC6454022 DOI: 10.1042/bsr20181709] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/18/2022] Open
Abstract
Innate immunity comprises several inflammation-related modulatory pathways which receive signals from an array of membrane-bound and cytoplasmic pattern recognition receptors (PRRs). The NLRs (NACHT (NAIP (neuronal apoptosis inhibitor protein), C2TA (MHC class 2 transcription activator), HET-E (incompatibility locus protein from Podospora anserina) and TP1 (telomerase-associated protein) and Leucine-Rich Repeat (LRR) domain containing proteins) relate to a large family of cytosolic innate receptors, involved in detection of intracellular pathogens and endogenous byproducts of tissue injury. These receptors may recognize pathogen-associated molecular patterns (PAMPs) and/or danger-associated molecular patterns (DAMPs), activating host responses against pathogen infection and cellular stress. NLR-driven downstream signals trigger a number of signaling circuitries, which may either initiate the formation of inflammasomes and/or activate nuclear factor κB (NF-κB), stress kinases, interferon response factors (IRFs), inflammatory caspases and autophagy. Disruption of those signals may lead to a number of pro-inflammatory conditions, eventually promoting the onset of human malignancies. In this review, we describe the structures and functions of the most well-defined NLR proteins and highlight their association and biological impact on a diverse number of cancers.
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FBXW7 in Cancer: What Has Been Unraveled Thus Far? Cancers (Basel) 2019; 11:cancers11020246. [PMID: 30791487 PMCID: PMC6406609 DOI: 10.3390/cancers11020246] [Citation(s) in RCA: 117] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 12/14/2022] Open
Abstract
: The FBXW7 (F-box with 7 tandem WD40) protein encoded by the gene FBXW7 is one of the crucial components of ubiquitin ligase called Skp1-Cullin1-F-box (SCF) complex that aids in the degradation of many oncoproteins via the ubiquitin-proteasome system (UPS) thus regulating cellular growth. FBXW7 is considered as a potent tumor suppressor as most of its target substrates can function as potential growth promoters, including c-Myc, Notch, cyclin E, c-JUN, and KLF5. Its regulators include p53, C/EBP-δ, Numb, microRNAs, Pin 1, Hes-5, BMI1, Ebp2. Mounting evidence has indicated the involvement of aberrant expression of FBXW7 for tumorigenesis. Moreover, numerous studies have also shown its role in cancer cell chemosensitization, thereby demonstrating the importance of FBXW7 in the development of curative cancer therapy. This comprehensive review emphasizes on the targets, functions, regulators and expression of FBXW7 in different cancers and its involvement in sensitizing cancer cells to chemotherapeutic drugs.
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Kheimar A, Trimpert J, Groenke N, Kaufer BB. Overexpression of cellular telomerase RNA enhances virus-induced cancer formation. Oncogene 2018; 38:1778-1786. [PMID: 30846849 DOI: 10.1038/s41388-018-0544-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/28/2018] [Accepted: 09/25/2018] [Indexed: 11/10/2022]
Abstract
The telomerase RNA subunit (TR) is overexpressed in many tumors; however, the contribution of TR in cancer formation remains elusive. The most frequent clinically diagnosed cancer in the animal kingdom is caused by the highly oncogenic herpesvirus Marek's disease virus (MDV). MDV encodes a TR (vTR) that plays an important role in virus-induced tumorigenesis and shares 88% sequence identity with its cellular homologue. To determine if the cellular TR possesses pro-oncogenic activity, we replaced vTR with the cellular homologue in the virus genome. Insertion of cellular TR resulted in a strong overexpression in virus infected cells, while virus replication was not affected. Strikingly, cellular TR promoted tumor formation as efficient as vTR, while tumorigenesis was severely impaired in the absence of vTR. Our data provide the first evidence that overexpression of cellular TR can contribute to tumor formation in vivo using this natural virus-host model for herpesvirus-induced oncogenesis.
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Affiliation(s)
- Ahmed Kheimar
- Institut für Virologie, Freie Universität Berlin, Robert von Ostertag-Straße 7-13, 14163, Berlin, Germany.,Department of Poultry Diseases, Faculty of Veterinary Medicine, Sohag University, 82424, Sohag, Egypt
| | - Jakob Trimpert
- Institut für Virologie, Freie Universität Berlin, Robert von Ostertag-Straße 7-13, 14163, Berlin, Germany
| | - Nicole Groenke
- Institut für Virologie, Freie Universität Berlin, Robert von Ostertag-Straße 7-13, 14163, Berlin, Germany
| | - Benedikt B Kaufer
- Institut für Virologie, Freie Universität Berlin, Robert von Ostertag-Straße 7-13, 14163, Berlin, Germany.
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Exploring major signaling cascades in melanomagenesis: a rationale route for targetted skin cancer therapy. Biosci Rep 2018; 38:BSR20180511. [PMID: 30166456 PMCID: PMC6167501 DOI: 10.1042/bsr20180511] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/14/2018] [Accepted: 08/24/2018] [Indexed: 02/06/2023] Open
Abstract
Although most melanoma cases may be treated by surgical intervention upon early diagnosis, a significant portion of patients can still be refractory, presenting low survival rates within 5 years after the discovery of the illness. As a hallmark, melanomas are highly prone to evolve into metastatic sites. Moreover, melanoma tumors are highly resistant to most available drug therapies and their incidence have increased over the years, therefore leading to public health concerns about the development of novel therapies. Therefore, researches are getting deeper in unveiling the mechanisms by which melanoma initiation can be triggered and sustained. In this context, important progress has been achieved regarding the roles and the impact of cellular signaling pathways in melanoma. This knowledge has provided tools for the development of therapies based on the intervention of signal(s) promoted by these cascades. In this review, we summarize the importance of major signaling pathways (mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)-Akt, Wnt, nuclear factor κ-light-chain-enhancer of activated B cell (NF-κB), Janus kinase (JAK)-signal transducer and activator of transcription (STAT), transforming growth factor β (TGF-β) and Notch) in skin homeostasis and melanoma progression. Available and developing melanoma therapies interfering with these signaling cascades are further discussed.
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49
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Xu X, Li Y, Bharath SR, Ozturk MB, Bowler MW, Loo BZL, Tergaonkar V, Song H. Structural basis for reactivating the mutant TERT promoter by cooperative binding of p52 and ETS1. Nat Commun 2018; 9:3183. [PMID: 30093619 PMCID: PMC6085347 DOI: 10.1038/s41467-018-05644-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 07/04/2018] [Indexed: 12/19/2022] Open
Abstract
Transcriptional factors ETS1/2 and p52 synergize downstream of non-canonical NF-κB signaling to drive reactivation of the −146C>T mutant TERT promoter in multiple cancer types, but the mechanism underlying this cooperativity remains unknown. Here we report the crystal structure of a ternary p52/ETS1/−146C>T TERT promoter complex. While p52 needs to associate with consensus κB sites on the DNA to function during non-canonical NF-κB signaling, we show that p52 can activate the −146C>T TERT promoter without binding DNA. Instead, p52 interacts with ETS1 to form a heterotetramer, counteracting autoinhibition of ETS1. Analogous to observations with the GABPA/GABPB heterotetramer, the native flanking ETS motifs are required for sustained activation of the −146C>T TERT promoter by the p52/ETS1 heterotetramer. These observations provide a unifying mechanism for transcriptional activation by GABP and ETS1, and suggest that genome-wide targets of non-canonical NF-κB signaling are not limited to those driven by consensus κB sequences. Incessant telomere synthesis in cancer cells depends on specific mutations in the TERT promoter, enabling its activation by transcription factors ETS1 and p52. Here, the authors elucidate the structural basis for p52/ETS1 binding to mutant TERT, suggesting a general mechanism for TERT reactivation in cancer.
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Affiliation(s)
- Xueyong Xu
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Yinghui Li
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Sakshibeedu R Bharath
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Mert Burak Ozturk
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore.,Department of Biochemistry, National University of Singapore, 14 Science Drive, Singapore, 117543, Singapore
| | - Matthew W Bowler
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, 38042, Grenoble, France.,Unit of Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, 71 Avenue des Martyrs, CS 90181, 38042, Grenoble, France
| | - Bryan Zong Lin Loo
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Vinay Tergaonkar
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore. .,Department of Biochemistry, National University of Singapore, 14 Science Drive, Singapore, 117543, Singapore. .,Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, 5001, SA, Australia.
| | - Haiwei Song
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Singapore. .,Department of Biochemistry, National University of Singapore, 14 Science Drive, Singapore, 117543, Singapore.
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El-Badawy A, Ghoneim NI, Nasr MA, Elkhenany H, Ahmed TA, Ahmed SM, El-Badri N. Telomerase reverse transcriptase coordinates with the epithelial-to-mesenchymal transition through a feedback loop to define properties of breast cancer stem cells. Biol Open 2018; 7:bio.034181. [PMID: 29907642 PMCID: PMC6078341 DOI: 10.1242/bio.034181] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Telomerase and its core component, telomerase reverse transcriptase (hTERT), are critical for stem cell compartment integrity. Normal adult stem cells have the longest telomeres in a given tissue, a property mediated by high hTERT expression and high telomerase enzymatic activity. In contrast, cancer stem cells (CSCs) have short telomeres despite high expression of hTERT, indicating that the role of hTERT in CSCs is not limited to telomere elongation and/or maintenance. The function of hTERT in CSCs remains poorly understood. Here, we knocked down hTERT expression in CSCs and observed a morphological shift to a more epithelial phenotype, suggesting a role for hTERT in the epithelial-to-mesenchymal transition (EMT) of CSCs. Therefore, in this study, we systematically explored the relationship between hTERT and EMT and identified a reciprocal, bi-directional feedback loop between hTERT and EMT in CSCs. We found that hTERT expression is mutually exclusive to the mesenchymal phenotype and that, reciprocally, loss of the mesenchymal phenotype represses hTERT expression. We also showed that hTERT plays a critical role in the expression of key CSC markers and nuclear β-catenin localization, increases the percentage of cells with side-population properties, and upregulates the CD133 expression. hTERT also promotes chemoresistance properties, tumorsphere formation and other important functional CSC properties. Subsequently, hTERT knockdown leads to the loss of the above advantages, indicating a loss of CSC properties. Our findings suggest that targeting hTERT might improve CSCs elimination by transitioning them from the aggressive mesenchymal state to a more steady epithelial state, thereby preventing cancer progression. Summary: This study describe a reciprocal, bi-directional feedback loop between hTERT and EMT to regulate properties of CSCs, suggesting that targeting hTERT may eliminate CSCs, thereby preventing cancer progression.
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Affiliation(s)
- Ahmed El-Badawy
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
| | - Nehal I Ghoneim
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
| | - Mohamed A Nasr
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
| | - Hoda Elkhenany
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt.,Department of Surgery, College of Veterinary Medicine, Alexandria University, Alexandria 22785, Egypt
| | - Toka A Ahmed
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
| | - Sara M Ahmed
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
| | - Nagwa El-Badri
- Center of Excellence for Stem Cells and Regenerative Medicine (CESC), Zewail City of Science and Technology, 6th of October City 12588, Egypt
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