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Subošić B, Kotur-Stevuljević J, Bogavac-Stanojević N, Zdravković V, Ješić M, Kovačević S, Đuričić I. Circulating Fatty Acids Associate with Metabolic Changes in Adolescents Living with Obesity. Biomedicines 2024; 12:883. [PMID: 38672237 PMCID: PMC11048623 DOI: 10.3390/biomedicines12040883] [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: 02/23/2024] [Revised: 03/20/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
Fatty acids play a crucial role in obesity development and in the comorbidities of obesity in both adults and children. This study aimed to assess the impact of circulating fatty acids on biomarkers of metabolic health of adolescents living with obesity. Parameters such as blood lipids, redox status, and leukocyte telomere length (rLTL) were measured alongside the proportions of individual fatty acids. The Mann-Whitney U test revealed that individuals with obesity exhibited an unfavorable lipid and redox status compared to the control normal weight group. The group with obesity also had lower plasma n-3 polyunsaturated fatty acids (PUFAs) and a higher ratio of n-6 to n-3 PUFAs than the control group. They also had a shorter rLTL, indicating accelerated biological aging. There was an inverse association of rLTL and plasma n-6-to-n-3 PUFA ratio. Future studies should explore the impact of recommended nutrition plans and increased physical activity on these parameters to determine if these interventions can enhance the health and well-being of adolescents with obesity, knowing that early obesity can track into adulthood.
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Affiliation(s)
- Branko Subošić
- Biochemical Laboratory, University Children’s Hospital, 11000 Belgrade, Serbia;
| | - Jelena Kotur-Stevuljević
- Department of Medical Biochemistry, Faculty of Pharmacy, University of Belgrade, 11221 Belgrade, Serbia; (J.K.-S.); (N.B.-S.)
| | - Nataša Bogavac-Stanojević
- Department of Medical Biochemistry, Faculty of Pharmacy, University of Belgrade, 11221 Belgrade, Serbia; (J.K.-S.); (N.B.-S.)
| | - Vera Zdravković
- Department of Endocrinology, Medical Faculty, University Children’s Hospital, 11000 Belgrade, Serbia; (V.Z.); (M.J.); (S.K.)
| | - Maja Ješić
- Department of Endocrinology, Medical Faculty, University Children’s Hospital, 11000 Belgrade, Serbia; (V.Z.); (M.J.); (S.K.)
| | - Smiljka Kovačević
- Department of Endocrinology, Medical Faculty, University Children’s Hospital, 11000 Belgrade, Serbia; (V.Z.); (M.J.); (S.K.)
| | - Ivana Đuričić
- Department of Bromatology, Faculty of Pharmacy, University of Belgrade, 11221 Belgrade, Serbia
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Wang H, Wang S, Wang H, Tang F, Chen D, Liang Y, Li Z. Amplification-free detection of telomerase activity at the single-cell level via Cas12a-lighting-up single microbeads (Cas12a-LSMBs). LAB ON A CHIP 2023; 23:4674-4679. [PMID: 37795981 DOI: 10.1039/d3lc00598d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
Telomerase overexpresses in almost all cancer cells and has been deemed a universal biomarker for cancer diagnosis and therapy. However, simple and ultrasensitive detection of telomerase activity in single-cells is still a huge challenge. Herein, we wish to report Cas12a-lighting up single microbeads (Cas12a-LSMBs) for ultrasensitive detection of telomerase activity without nucleic acid amplification. In this platform, single-strand DNA reporter (ssDNA reporter)-functionalized single-microbeads (functionalized-SMBs) are employed as a reactor for the trans-cleavage of telomerase-activated CRISPR/Cas12a as well as a reporting unit for fluorescence signal enrichment and visualization. Due to the space-confined effect and signal enrichment mechanism on the surface of the functionalized SMBs, the Cas12a-LSMBs can accurately detect telomerase activity in crude cell lysates with high specificity. Importantly, we have demonstrated that the Cas12a-LSMBs are a reliable and practical tool to detect telomerase activity in single cells and investigate cellular heterogeneity of telomerase activity from cell-to-cell variations.
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Affiliation(s)
- Honghong Wang
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
| | - Shuhui Wang
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
| | - Hui Wang
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
| | - Fu Tang
- School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Desheng Chen
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
| | - Yuanwen Liang
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
| | - Zhengping Li
- Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
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3
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Han X, Hirschel A, Tsapekos M, Perez D, Vollmer D. In Vitro Assessment of Gold Nanoparticles on Telomerase Activity and Telomere Length in Human Fibroblasts. Int J Mol Sci 2023; 24:14273. [PMID: 37762576 PMCID: PMC10532081 DOI: 10.3390/ijms241814273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Telomerase activity coincides with lengthening of the ends of chromosomes known as telomeres. Telomere length is used as a marker for cellular aging. Telomeres shorten over time as cells divide, and certain bioactive compounds such as gold nanoparticles (AuNPs) may slow the shortening of telomeres by increasing telomerase activity. The objective of the present study is to assess the effect of AuNPs on telomerase activity and telomere length in human fibroblasts. Telomerase activity was measured using enzyme-linked immunosorbent assay (ELISA) in primary human lung fibroblasts (IMR90) and using quantitative PCR-based telomeric repeat amplification protocol (Q-TRAP) in primary human dermal fibroblasts, neonatal (HDFn). Telomere length was determined by Telomere Analysis Technology (TAT®)assay in HDFn. In IMR90, all AuNP treatments showed significant increases in telomerase activity when compared to earlier passages. HDFn treated with AuNPs at 0 ppm, 0.05 ppm, 0.5 ppm, or 5 ppm did not show significant differences in telomerase activity compared to the control group. Significant differences in telomere length in HDFn were observed at 2 weeks of 0.05 and 0.5 ppm AuNPs under oxidative culture conditions as compared to the control group. The study showed preliminary evidence that AuNPs may increase telomerase activity and decelerate the shortening of telomeres in human fibroblasts, suggesting its potential anti-aging effects, which warrants further investigation.
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Affiliation(s)
- Xuesheng Han
- Scientific Research Division, 4Life Research, Sandy, UT 84070, USA (D.V.)
| | - Alice Hirschel
- Scientific Research Division, 4Life Research, Sandy, UT 84070, USA (D.V.)
| | | | | | - David Vollmer
- Scientific Research Division, 4Life Research, Sandy, UT 84070, USA (D.V.)
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Ries A, Slany A, Pirker C, Mader JC, Mejri D, Mohr T, Schelch K, Flehberger D, Maach N, Hashim M, Hoda MA, Dome B, Krupitza G, Berger W, Gerner C, Holzmann K, Grusch M. Primary and hTERT-Transduced Mesothelioma-Associated Fibroblasts but Not Primary or hTERT-Transduced Mesothelial Cells Stimulate Growth of Human Mesothelioma Cells. Cells 2023; 12:2006. [PMID: 37566084 PMCID: PMC10417280 DOI: 10.3390/cells12152006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/12/2023] Open
Abstract
Pleural mesothelioma (PM) is an aggressive malignancy that develops in a unique tumor microenvironment (TME). However, cell models for studying the TME in PM are still limited. Here, we have generated and characterized novel human telomerase reverse transcriptase (hTERT)-transduced mesothelial cell and mesothelioma-associated fibroblast (Meso-CAF) models and investigated their impact on PM cell growth. Pleural mesothelial cells and Meso-CAFs were isolated from tissue of pneumothorax and PM patients, respectively. Stable expression of hTERT was induced by retroviral transduction. Primary and hTERT-transduced cells were compared with respect to doubling times, hTERT expression and activity levels, telomere lengths, proteomes, and the impact of conditioned media (CM) on PM cell growth. All transduced derivatives exhibited elevated hTERT expression and activity, and increased mean telomere lengths. Cell morphology remained unchanged, and the proteomes were similar to the corresponding primary cells. Of note, the CM of primary and hTERT-transduced Meso-CAFs stimulated PM cell growth to the same extent, while CM derived from mesothelial cells had no stimulating effect, irrespective of hTERT expression. In conclusion, all new hTERT-transduced cell models closely resemble their primary counterparts and, hence, represent valuable tools to investigate cellular interactions within the TME of PM.
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Affiliation(s)
- Alexander Ries
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Astrid Slany
- Department of Analytical Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria; (A.S.); (J.C.M.); (C.G.)
| | - Christine Pirker
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Johanna C. Mader
- Department of Analytical Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria; (A.S.); (J.C.M.); (C.G.)
| | - Doris Mejri
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Thomas Mohr
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
- Department of Analytical Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria; (A.S.); (J.C.M.); (C.G.)
- Joint Metabolome Facility, University of Vienna and Medical University of Vienna, Waehringer Guertel 38, 1090 Vienna, Austria
- ScienceConsult—DI Thomas Mohr KG, Enzianweg 10a, 2353 Guntramsdorf, Austria
| | - Karin Schelch
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
- Department of Thoracic Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; (M.A.H.); (B.D.)
| | - Daniela Flehberger
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Nadine Maach
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Muhammad Hashim
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Mir Alireza Hoda
- Department of Thoracic Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; (M.A.H.); (B.D.)
| | - Balazs Dome
- Department of Thoracic Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; (M.A.H.); (B.D.)
- National Korányi Institute of Pulmonology, Korányi Frigyes u. 1, 1122 Budapest, Hungary
- Department of Thoracic Surgery, National Institute of Oncology, Semmelweis University, Rath Gyorgy u. 7-9, 1122 Budapest, Hungary
- Department of Translational Medicine, Lund University, Sölvegatan 19, 22184 Lund, Sweden
| | - Georg Krupitza
- Department of Pathology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria;
| | - Walter Berger
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Christopher Gerner
- Department of Analytical Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria; (A.S.); (J.C.M.); (C.G.)
| | - Klaus Holzmann
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
| | - Michael Grusch
- Center for Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, 1090 Vienna, Austria; (A.R.); (C.P.); (D.M.); (T.M.); (K.S.); (D.F.); (N.M.); (M.H.); (W.B.); (K.H.)
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Zhao X, Luo D, Liu T, Zhang H, Xie Y, Kong W. BIBR1532 Affects Endometrial Cell Proliferation, Migration, and Invasion in Endometriosis via Telomerase Inhibition and MAPK Signaling. Gynecol Obstet Invest 2023; 88:226-239. [PMID: 37429261 DOI: 10.1159/000530460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 02/27/2023] [Indexed: 07/12/2023]
Abstract
OBJECTIVES The effect of telomerase inhibitor BIBR1532 on endometriotic cells was investigated to explore the inhibitory effect of targeting telomerase on endometriosis. DESIGN In vitro primary cell culture study. Participants/Materials: Primary endometrial cells derived from eutopic and ectopic endometrium in patients with endometriosis. SETTING The study was conducted in the university hospital. METHODS Paired eutopic and ectopic endometrial cells were collected from 6 patients from January 2018 to July 2021. A TRAP assay was performed to detect the telomerase activity of the cells. MTT, cell cycle, apoptosis, migration, and invasion assays were performed to study the inhibitory effect of BIBR1532. Enrichment analysis was performed to identify the key pathways involved in endometriosis progression and telomerase action. Then, Western blotting was used to investigate the expression of related proteins. RESULTS BIBR1532 treatment significantly inhibited the growth of eutopic and ectopic endometrial cells, with apoptosis and cell cycle signaling involved. Migration and invasion, important characteristics for the establishment of ectopic lesions, were also inhibited by BIBR1532. The MAPK signaling cascade, related to telomerase and endometriosis, was decreased in eutopic and ectopic endometrial stromal cells with the treatment of BIBR1532. LIMITATIONS The severe side effects of telomerase inhibitors might be the main obstacle to clinical application, so it is necessary to find better drug delivery methods in vivo. CONCLUSIONS The telomerase inhibitor BIBR1532 affects endometrial cell proliferation, migration, and invasion in endometriosis.
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Affiliation(s)
- Xiaoling Zhao
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - Dan Luo
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - Tingting Liu
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - He Zhang
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - Yunkai Xie
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
| | - Weimin Kong
- Department of Gynecologic Oncology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing, China
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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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Moses EJ, Azlan A, Khor KZ, Mot YY, Mohamed S, Seeni A, Barneh F, Heidenreich O, Yusoff N. A RUNX1/ETO-SKP2-CDKN1B axis regulates expression of telomerase in t (8;21) acute myeloid leukemia. Cell Mol Life Sci 2023; 80:70. [PMID: 36820913 PMCID: PMC11071865 DOI: 10.1007/s00018-023-04713-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 01/27/2023] [Accepted: 01/30/2023] [Indexed: 02/24/2023]
Abstract
The fusion oncoprotein RUNX1/ETO which results from the chromosomal translocation t (8;21) in acute myeloid leukemia (AML) is an essential driver of leukemic maintenance. We have previously shown that RUNX1/ETO knockdown impairs expression of the protein component of telomerase, TERT. However, the underlying molecular mechanism of how RUNX1/ETO controls TERT expression has not been fully elucidated. Here we show that RUNX1/ETO binds to an intergenic region 18 kb upstream of the TERT transcriptional start site and to a site located in intron 6 of TERT. Loss of RUNX1/ETO binding precedes inhibition of TERT expression. Repression of TERT expression is also dependent on the destabilization of the E3 ubiquitin ligase SKP2 and the resultant accumulation of the cell cycle inhibitor CDKN1B, that are both associated with RUNX1/ETO knockdown. Increased CDKN1B protein levels ultimately diminished TERT transcription with E2F1/Rb involvement. Collectively, our results show that RUNX1/ETO controls TERT expression directly by binding to its locus and indirectly via a SKP2-CDKN1B-E2F1/Rb axis.
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Affiliation(s)
- Emmanuel J Moses
- Department of Biomedical Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia.
| | - Adam Azlan
- Department of Biomedical Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - Kang Zi Khor
- Department of Biomedical Sciences, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - Yee Yik Mot
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - Saleem Mohamed
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - Azman Seeni
- Department of Toxicology, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
| | - Farnaz Barneh
- Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands
| | - Olaf Heidenreich
- Princess Maxima Center for Pediatric Oncology, Utrecht, The Netherlands.
- Wolfson Childhood Cancer Research Centre, Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, UK.
| | - Narazah Yusoff
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Malaysia
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Marinaccio J, Micheli E, Udroiu I, Di Nottia M, Carrozzo R, Baranzini N, Grimaldi A, Leone S, Moreno S, Muzzi M, Sgura A. TERT Extra-Telomeric Roles: Antioxidant Activity and Mitochondrial Protection. Int J Mol Sci 2023; 24:ijms24054450. [PMID: 36901881 PMCID: PMC10002448 DOI: 10.3390/ijms24054450] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/18/2023] [Accepted: 02/20/2023] [Indexed: 03/05/2023] Open
Abstract
Telomerase reverse transcriptase (TERT) is the catalytic subunit of telomerase holoenzyme, which adds telomeric DNA repeats on chromosome ends to counteract telomere shortening. In addition, there is evidence of TERT non-canonical functions, among which is an antioxidant role. In order to better investigate this role, we tested the response to X-rays and H2O2 treatment in hTERT-overexpressing human fibroblasts (HF-TERT). We observed in HF-TERT a reduced induction of reactive oxygen species and an increased expression of the proteins involved in the antioxidant defense. Therefore, we also tested a possible role of TERT inside mitochondria. We confirmed TERT mitochondrial localization, which increases after oxidative stress (OS) induced by H2O2 treatment. We next evaluated some mitochondrial markers. The basal mitochondria quantity appeared reduced in HF-TERT compared to normal fibroblasts and an additional reduction was observed after OS; nevertheless, the mitochondrial membrane potential and morphology were better conserved in HF-TERT. Our results suggest a protective function of TERT against OS, also preserving mitochondrial functionality.
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Affiliation(s)
| | - Emanuela Micheli
- Department of Science, University “ROMA TRE”, 00146 Rome, Italy
- Correspondence:
| | - Ion Udroiu
- Department of Science, University “ROMA TRE”, 00146 Rome, Italy
| | - Michela Di Nottia
- Unit of Muscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children’s Hospital IRCCS, 00146 Rome, Italy
| | - Rosalba Carrozzo
- Unit of Muscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children’s Hospital IRCCS, 00146 Rome, Italy
| | - Nicolò Baranzini
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Annalisa Grimaldi
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Stefano Leone
- Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Sandra Moreno
- Department of Science, University “ROMA TRE”, 00146 Rome, Italy
- IRCCS Santa Lucia Foundation, 00179 Rome, Italy
| | - Maurizio Muzzi
- Department of Science, University “ROMA TRE”, 00146 Rome, Italy
- IRCCS Santa Lucia Foundation, 00179 Rome, Italy
| | - Antonella Sgura
- Department of Science, University “ROMA TRE”, 00146 Rome, Italy
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In Vitro Determination of the Skin Anti-Aging Potential of Four-Component Plant-Based Ingredient. Molecules 2022; 27:molecules27228101. [PMID: 36432202 PMCID: PMC9697998 DOI: 10.3390/molecules27228101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/11/2022] [Accepted: 11/16/2022] [Indexed: 11/23/2022] Open
Abstract
The beauty industry is actively searching for solutions to prevent skin aging. Some of the crucial elements protecting cells from the aging process are telomere shortening, telomerase expression, cell senescence, and homeostasis of the redox system. Modification of these factors using natural antioxidants is an appealing way to support healthy skin aging. Therefore, in this study, we sought to investigate the antiaging efficacy of a specific combination of four botanical extracts (pomegranate, sweet orange, Cistanche and Centella asiatica) with proven antioxidant properties. To this end, normal human dermal fibroblasts were used as a cell model and the following studies were performed: cell proliferation was established by means of the MTT assay and the intracellular ROS levels in stress-induced premature senescence fibroblasts; telomere length measurement was performed under standard cell culture conditions using qPCR and under oxidative stress conditions using a variation of the Q-FISH technique; telomerase activity was examined by means of Q-TRAP; and AGE quantification was completed by means of ELISA assay in UV-irradiated fibroblasts. As a result, the botanical blend significantly reversed the H2O2-induced decrease in cell viability and reduced H2O2-induced ROS. Additionally, the presence of the botanical ingredient reduced the telomere shortening rate in both stressed and non-stressed replicating fibroblasts, and under oxidative stress conditions, the fibroblasts presented a higher median and 20th percentile telomere length, as well as a lower percentage of short telomeres (<3 Kbp) compared with untreated fibroblasts. Furthermore, the ingredient transiently increased relative telomerase activity after 24 h and prevented the accumulation of UVR-induced glycated species. The results support the potential use of this four-component plant-based ingredient as an antiaging agent.
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Ahmadi M, Barnard S, Ainsbury E, Kadhim M. Early Responses to Low-Dose Ionizing Radiation in Cellular Lens Epithelial Models. Radiat Res 2021; 197:78-91. [PMID: 34324666 DOI: 10.1667/rade-20-00284.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 07/06/2021] [Indexed: 11/03/2022]
Abstract
Cataract is the leading cause of visual impairment which can result in blindness. Cataract formation has been associated with radiation exposure; however, the mechanistic understanding of this phenomenon is still lacking. The goal of this study was to investigate mechanisms of cataract induction in isolated lens epithelial cells (LEC) exposed to ionizing radiation. Human LECs from different genetic backgrounds (SV40 immortalized HLE-B3 and primary HLEC cells) were exposed to varying doses of 137Cs gamma rays (0, 0.1, 0.25 and 0.5 Gy), at low (0.065 Gy/min) and higher (0.3 Gy/min) dose rates. Different assays were used to measure LEC response for, e.g., viability, oxidative stress, DNA damage studies, senescence and changes to telomere length/telomerase activity at two time points (1 h and 24 h, or 24 h and 15 days, depending on the type of assay and expected response time). The viability of cells decreased in a dose-dependent manner within 24 h of irradiation. Measurement of reactive oxygen species showed an increase at 1 h postirradiation, which was alleviated within 24 h. This was consistent with DNA damage results showing high DNA damage after 1 h postirradiation which reduced significantly (but not completely) within 24 h. Induction of senescence was also observed 15 days postirradiation, but this was not attributed to telomere erosion or telomerase activity reduction. Overall, these findings provide a mechanistic understanding of low-dose radiation-induced cataractogenesis which will ultimately help to inform judgements on the magnitude of risk and improve existing radiation protection procedures.
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Affiliation(s)
- Maryam Ahmadi
- Genomic Instability and Cell Communication Research Group, Department of Biological and Medical Science, Oxford Brookes University, Oxford, United Kingdom.,Kidney Genetics Group, Academic Unit of Nephrology, The Medical School, Royal Hallamshire Hospital, Sheffield, United Kingdom
| | - Stephen Barnard
- Public Health England, Centre for Radiation, Chemical and Environmental Hazards, Oxford, United Kingdom
| | - Elizabeth Ainsbury
- Public Health England, Centre for Radiation, Chemical and Environmental Hazards, Oxford, United Kingdom
| | - Munira Kadhim
- Genomic Instability and Cell Communication Research Group, Department of Biological and Medical Science, Oxford Brookes University, Oxford, United Kingdom
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11
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Robinson NJ, Miyagi M, Scarborough JA, Scott JG, Taylor DJ, Schiemann WP. SLX4IP promotes RAP1 SUMOylation by PIAS1 to coordinate telomere maintenance through NF-κB and Notch signaling. Sci Signal 2021; 14:eabe9613. [PMID: 34187905 PMCID: PMC8353884 DOI: 10.1126/scisignal.abe9613] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The maintenance of telomere length supports repetitive cell division and therefore plays a central role in cancer development and progression. Telomeres are extended by either the enzyme telomerase or the alternative lengthening of telomeres (ALT) pathway. Here, we found that the telomere-associated protein SLX4IP dictates telomere proteome composition by recruiting and activating the E3 SUMO ligase PIAS1 to the SLX4 complex. PIAS1 SUMOylated the telomere-binding protein RAP1, which disrupted its interaction with the telomere-binding protein TRF2 and facilitated its nucleocytoplasmic shuttling. In the cytosol, RAP1 bound to IκB kinase (IKK), resulting in activation of the transcription factor NF-κB and its induction of Jagged-1 expression, which promoted Notch signaling and the institution of ALT. This axis could be targeted therapeutically in ALT-driven cancers and in tumor cells that develop resistance to antitelomerase therapies. Our results illuminate the mechanisms underlying SLX4IP-dependent telomere plasticity and demonstrate the role of telomere proteins in directly coordinating intracellular signaling and telomere maintenance dynamics.
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Affiliation(s)
- Nathaniel J Robinson
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Masaru Miyagi
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Jessica A Scarborough
- Department of Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jacob G Scott
- Department of Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Derek J Taylor
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - William P Schiemann
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA.
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12
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Synergistic activation of mutant TERT promoter by Sp1 and GABPA in BRAF V600E-driven human cancers. NPJ Precis Oncol 2021; 5:3. [PMID: 33483600 PMCID: PMC7822828 DOI: 10.1038/s41698-020-00140-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 12/01/2020] [Indexed: 01/30/2023] Open
Abstract
The activating TERT promoter mutations and BRAFV600E mutation are well-established oncogenic alterations in human cancers. Coexistence of BRAFV600E and TERT promoter mutations is frequently found in multiple cancer types, and is strongly associated with poor patient prognosis. Although the BRAFV600E-elicited activation of ERK has been demonstrated to contribute to TERT reactivation by maintaining an active chromatin state, it still remains to be addressed how activated ERK is selectively recruited to mutant TERT promoter. Here, we report that transcription factor GABPA mediates the regulation of BRAFV600E/MAPK signaling on TERT reactivation by selectively recruiting activated ERK to mutant TERT promoter, where activated ERK can phosphorylate Sp1, thereby resulting in HDAC1 dissociation and an active chromatin state. Meanwhile, phosphorylated Sp1 further enhances the binding of GABPA to mutant TERT promoter. Taken together, our data indicate that GABPA and Sp1 synergistically activate mutant TERT promoter, contributing to tumorigenesis and cancer progression, particularly in the BRAFV600E-driven human cancers. Thus, our findings identify a direct mechanism that bridges two frequent oncogenic alterations together in TERT reactivation.
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13
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Pinto TNC, Fernandes JR, Arruda LB, Duarte AJDS, Benard G. Cost-Effective Trap qPCR Approach to Evaluate Telomerase Activity: an Important Tool for Aging, Cancer, and Chronic Disease Research. Clinics (Sao Paulo) 2021; 76:e2432. [PMID: 33567048 PMCID: PMC7847253 DOI: 10.6061/clinics/2021/e2432] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/20/2020] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES Telomeres are a terminal "DNA cap" that prevent chromosomal fusion and degradation. However, aging is inherent to life, and so is the loss of terminal sequences. Telomerase is a specialized reverse transcriptase encoded by self-splicing introns that counteract chromosome erosion. Telomerase activity is observed during early embryonic development, but after the blastocyst stage, the expression of telomerase reduces. The consequences of either insufficient or unrestrained telomerase activity underscore the importance of ongoing studies aimed at elucidating the regulation of telomerase activity in humans. In the present study, we aimed to standardize a simplified telomerase repeat-amplification protocol (TRAP) assay to detect telomerase activity in unstimulated and PHA-stimulated mononuclear cells. METHODS AND RESULTS Our optimized qPCR-based can efficiently evaluate telomerase activity. Quantification of protein and DNA between unstimulated and PHA-stimulated peripheral blood mononuclear cells revealed cellular activation and cell-cycle entry. The assay also showed that relative telomerase activity is significantly different between these two conditions, supporting the applicability of the assay. Furthermore, our findings corroborated that telomerase activity decreases with age. CONCLUSIONS Telomeres and telomerase are implicated in aging and development of chronic diseases and cancer; however, difficulty in accessing commercial kits to investigate these aspects is a critical constraint in health surveillance studies. Our optimized assay was successfully used to differentiate telomerase activity between unstimulated and stimulated cells, clearly showing the reactivation of telomerase upon cell activation. This assay is affordable, reproducible, and can be executed in resource-limited settings.
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Affiliation(s)
- Thalyta Nery Carvalho Pinto
- Laboratorio de Dermatologia e Imunodeficiencias (LIM56), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
- *Corresponding author. E-mail:
| | - Juliana Ruiz Fernandes
- Laboratorio de Dermatologia e Imunodeficiencias (LIM56), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
- *Corresponding author. E-mail:
| | - Liã Barbara Arruda
- Division of Infection and Immunity, Center for Clinical Microbiology, Royal Free Hospital Campus, London, University College London, Division of Infection and Immunity, Center for Clinical Microbiology, Royal Free Hospital Campus, LondonUniversity College London UK
| | - Alberto José da Silva Duarte
- Laboratorio de Dermatologia e Imunodeficiencias (LIM56), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
| | - Gil Benard
- Laboratorio de Dermatologia e Imunodeficiencias (LIM56), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, BR
- Laboratorio de Micologia Medica, Instituto de Medicina Tropical, Universidade de Sao Paulo, Sao Paulo, SP, BR
- *Corresponding author. E-mail:
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14
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Effects of a complex mixture prepared from agrimonia, houttuynia, licorice, peony, and phellodendron on human skin cells. Sci Rep 2020; 10:22132. [PMID: 33335246 PMCID: PMC7746697 DOI: 10.1038/s41598-020-79301-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 12/07/2020] [Indexed: 01/02/2023] Open
Abstract
Active ingredients derived from natural sources are widely utilized in many industries. Cosmetic active ingredients are largely derived from various plants. In this study, we examined whether a mixture of plant extracts obtained from agrimonia, houttuynia, licorice, peony, and phellodendron (hereafter AHLPP), which are well-known for their effects on skin, could affect skin barrier function, inflammation, and aging in human skin cells. We also determined whether AHLPP extracts sterilized using γ-irradiation (to avoid preservatives) retained their skin cell regulating activity. The AHLPP mixture could downregulate representative pro-inflammatory cytokines including IL 1-β and IL 7. Procollagen peptide synthesis was also increased by AHLPP treatment along with mRNA upregulation of barrier proteins such as filaggrin and desmoplakin. The AHLPP mixture showed an anti-aging effect by significantly upregulating telomerase activity in human keratinocytes. We further observed TERT upregulation and CDKN1B downregulation, implying a weakening of pro-aging signal transduction. Co-cultivation of a hydrogel polymer containing the AHLPP mixture with human skin cells showed an alteration in skin-significant genes such as FLG, which encodes filaggrin. Thus, the AHLPP mixture with or without γ-irradiation can be utilized for skin protection as it alters the expression of some significant genes in human skin cells.
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15
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Ahmed R, Miners KL, Lahoz-Beneytez J, Jones RE, Roger L, Baboonian C, Zhang Y, Wang ECY, Hellerstein MK, McCune JM, Baird DM, Price DA, Macallan DC, Asquith B, Ladell K. CD57 + Memory T Cells Proliferate In Vivo. Cell Rep 2020; 33:108501. [PMID: 33326780 PMCID: PMC7758161 DOI: 10.1016/j.celrep.2020.108501] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/26/2020] [Accepted: 11/18/2020] [Indexed: 01/15/2023] Open
Abstract
A central paradigm in the field of lymphocyte biology asserts that replicatively senescent memory T cells express the carbohydrate epitope CD57. These cells nonetheless accumulate with age and expand numerically in response to persistent antigenic stimulation. Here, we use in vivo deuterium labeling and ex vivo analyses of telomere length, telomerase activity, and intracellular expression of the cell-cycle marker Ki67 to distinguish between two non-exclusive scenarios: (1) CD57+ memory T cells do not proliferate and instead arise via phenotypic transition from the CD57- memory T cell pool; and/or (2) CD57+ memory T cells self-renew via intracompartmental proliferation. Our results provide compelling evidence in favor of the latter scenario and further suggest in conjunction with mathematical modeling that self-renewal is by far the most abundant source of newly generated CD57+ memory T cells. Immunological memory therefore appears to be intrinsically sustainable among highly differentiated subsets of T cells that express CD57.
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Affiliation(s)
- Raya Ahmed
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK
| | - Kelly L Miners
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | | | - Rhiannon E Jones
- Division of Cancer and Genetics, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Laureline Roger
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Christina Baboonian
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK
| | - Yan Zhang
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK
| | - Eddie C Y Wang
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Marc K Hellerstein
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720, USA
| | - Joseph M McCune
- HIV Frontiers Program, Global Health Innovative Technology Solutions, Bill & Melinda Gates Foundation, Seattle, WA 98109, USA
| | - Duncan M Baird
- Division of Cancer and Genetics, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - David A Price
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK; Systems Immunity Research Institute, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK.
| | - Derek C Macallan
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK; St George's University Hospitals NHS Foundation Trust, London SW17 0QT, UK.
| | - Becca Asquith
- Department of Infectious Disease, Imperial College London, London W2 1PG, UK.
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK; Neonatal Unit, Singleton Hospital, Swansea Bay University Health Board, Swansea SA2 8QA, UK.
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16
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Samuel P, Tsapekos M, de Pedro N, Liu AG, Casey Lippmeier J, Chen S. Ergothioneine Mitigates Telomere Shortening under Oxidative Stress Conditions. J Diet Suppl 2020; 19:212-225. [PMID: 33287595 DOI: 10.1080/19390211.2020.1854919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Shortened telomeres are associated with aging and age-related diseases. Oxidative stress is thought to be a major contributor to telomere shortening, and antioxidants may be able to mitigate these effects. Ergothioneine is a naturally occurring amino acid with potent antioxidant properties. In order to investigate ergothioneine's effects on telomere length, we cultured primary human fibroblasts under standard and oxidative (10 µM H2O2) conditions and treated cells with 0.04, 0.1, 0.3, or 1.0 mg/ml ergothioneine for 8 weeks. Telomere length measurements were performed using high-throughput quantitative fluorescent in situ hybridization (HT Q-FISH). Treatment with ergothioneine transiently increased relative telomerase activity after 24 h (p < 0.05 for all concentrations). Under oxidative conditions, ergothioneine treatment resulted in significantly longer median telomere length and 20th percentile telomere length, and significantly reduced the percentage of short telomeres (<3 kilobase pairs) for all treatment concentrations after 8 weeks. Telomere shortening rate was also reduced. Overall, ergothioneine demonstrated beneficial effects by decreasing the rate of telomere shortening and preserving telomere length under oxidative stress conditions. Our data support a potential role for ergothioneine in oxidative stress-related conditions and healthy aging.
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Affiliation(s)
| | | | | | - Ann G Liu
- Freelance Medical Writer, Valencia, CA, USA
| | | | - Steven Chen
- Blue California, Rancho Santa Margarita, CA, USA
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17
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DiMaio TA, Vogt DT, Lagunoff M. KSHV requires vCyclin to overcome replicative senescence in primary human lymphatic endothelial cells. PLoS Pathog 2020; 16:e1008634. [PMID: 32555637 PMCID: PMC7326280 DOI: 10.1371/journal.ppat.1008634] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 06/30/2020] [Accepted: 05/14/2020] [Indexed: 12/13/2022] Open
Abstract
Kaposi's Sarcoma Herpesvirus (KSHV) is present in the main tumor cells of Kaposi's Sarcoma (KS), the spindle cells, which are of endothelial origin. KSHV is also associated with two B-cell lymphomas, Primary Effusion Lymphoma (PEL) and Multicentric Castleman's Disease. In KS and PEL, KSHV is primarily latent in the infected cells, expressing only a few genes. Although KSHV infection is required for KS and PEL, it is unclear how latent gene expression contributes to their formation. Proliferation of cancer cells occurs despite multiple checkpoints intended to prevent dysregulated cell growth. The first of these checkpoints, caused by shortening of telomeres, results in replicative senescence, where cells are metabolically active, but no longer divide. We found that human dermal lymphatic endothelial cells (LECs) are more susceptible to KSHV infection than their blood-specific endothelial cell counterparts and maintain KSHV latency to higher levels during passage. Importantly, KSHV infection of human LECs but not human BECs promotes their continued proliferation beyond this first checkpoint of replicative senescence. The latently expressed viral cyclin homolog is essential for KSHV-induced bypass of senescence in LECs. These data suggest that LECs may be an important reservoir for KSHV infection and may play a role during KS tumor development and that the viral cyclin is a critical oncogene for this process.
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Affiliation(s)
- Terri A. DiMaio
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Daniel T. Vogt
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Michael Lagunoff
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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18
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Huang S, Zhang Q, Yao H, Wang W, Zhang JR, Zhu JJ. Quantitative Detection and Imaging of Multiple Biological Molecules in Living Cells for Cell Screening. ACS Sens 2020; 5:1149-1157. [PMID: 32164417 DOI: 10.1021/acssensors.0c00170] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Because of insufficient information, a single biomarker is not sufficient for early diagnosis of cancer, whereas sensitive and selective detection of multiple biomolecules can significantly reduce analysis time, sample size, and accurately perform cell screening in early cancer. Therefore, the development of a noninvasive strategy that can simultaneously quantify multiple biomarkers (i.e., nucleic acids, proteins, and small molecules) in a single cell is particularly important. Herein, a universal sensing system (functional DNA@mesoporous silica nanoparticles (MSN)-Black Hole Quencher-rhodamine 6G (RhB), FDSBR), which is based on the combination of functionalized DNA and smart responsive nanomaterial, was successfully constructed. After incubation with the cells, different types of targets trigger the strand displacement reaction to release the fluorophore-labeled nucleic acids as the output signals to reflect the intracellular level of the telomerase and adenosine triphosphate (ATP), respectively. Simultaneously, intracellular miR-21 can be clearly indicated by the restored fluorescence of RhB when the caged double-stranded DNA was substituted into single-stranded DNA to open the pore. The concentrations of intracellular telomerase, miR-21, and ATP were identified successfully in three cell lines at the single-cell level. The results show that the contents of three biomolecules have significant differences in the three model cell lines and provide a promising route for developing innovative early disease diagnosis and cell screening assay.
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Affiliation(s)
- Shan Huang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Qianying Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Huiqin Yao
- Department of Chemistry, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan 750004, China
| | - Wenjing Wang
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Jian-Rong Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
- School of Chemistry and Life Science, Nanjing University Jinling College, Nanjing 210089, China
| | - Jun-Jie Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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19
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Ng WH, Yong YK, Ramasamy R, Ngalim SH, Lim V, Shaharuddin B, Tan JJ. Human Wharton's Jelly-Derived Mesenchymal Stem Cells Minimally Improve the Growth Kinetics and Cardiomyocyte Differentiation of Aged Murine Cardiac c-kit Cells in In Vitro without Rejuvenating Effect. Int J Mol Sci 2019; 20:ijms20225519. [PMID: 31698679 PMCID: PMC6887783 DOI: 10.3390/ijms20225519] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 09/30/2019] [Accepted: 09/30/2019] [Indexed: 01/09/2023] Open
Abstract
Cardiac c-kit cells show promise in regenerating an injured heart. While heart disease commonly affects elderly patients, it is unclear if autologous cardiac c-kit cells are functionally competent and applicable to these patients. This study characterised cardiac c-kit cells (CCs) from aged mice and studied the effects of human Wharton’s Jelly-derived mesenchymal stem cells (MSCs) on the growth kinetics and cardiac differentiation of aged CCs in vitro. CCs were isolated from 4-week- and 18-month-old C57/BL6N mice and were directly co-cultured with MSCs or separated by transwell insert. Clonogenically expanded aged CCs showed comparable telomere length to young CCs. However, these cells showed lower Gata4, Nkx2.5, and Sox2 gene expressions, with changes of 2.4, 3767.0, and 4.9 folds, respectively. Direct co-culture of both cells increased aged CC migration, which repopulated 54.6 ± 4.4% of the gap area as compared to aged CCs with MSCs in transwell (42.9 ± 2.6%) and CCs without MSCs (44.7 ± 2.5%). Both direct and transwell co-culture improved proliferation in aged CCs by 15.0% and 16.4%, respectively, as traced using carboxyfluorescein succinimidyl ester (CFSE) for three days. These data suggest that MSCs can improve the growth kinetics of aged CCs. CCs retaining intact telomere are present in old hearts and could be obtained based on their self-renewing capability. Although these aged CCs with reduced growth kinetics are improved by MSCs via cell–cell contact, the effect is minimal.
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Affiliation(s)
- Wai Hoe Ng
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia; (W.H.N.); (S.H.N.); (V.L.); (B.S.)
| | - Yoke Keong Yong
- Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor Darul Ehsan, Malaysia;
| | - Rajesh Ramasamy
- Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor Darul Ehsan, Malaysia;
| | - Siti Hawa Ngalim
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia; (W.H.N.); (S.H.N.); (V.L.); (B.S.)
| | - Vuanghao Lim
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia; (W.H.N.); (S.H.N.); (V.L.); (B.S.)
| | - Bakiah Shaharuddin
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia; (W.H.N.); (S.H.N.); (V.L.); (B.S.)
| | - Jun Jie Tan
- Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200, Kepala Batas, Penang, Malaysia; (W.H.N.); (S.H.N.); (V.L.); (B.S.)
- Correspondence: ; Tel.: +045622422
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20
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Yuan T, Zhao W, Niu Y, Fu Y, Lu L, Niu D. Exploration of the temporal-spatial expression pattern and DNA methylation-related regulation of the duck telomerase reverse transcriptase gene. Poult Sci 2019; 98:3257-3267. [PMID: 31064004 DOI: 10.3382/ps/pez240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 04/09/2019] [Indexed: 12/14/2022] Open
Abstract
Telomerase reverse transcriptase (TERT) is a catalytic subunit of telomerase that adds TTAGGG repeats to the 3'-overhang of telomeres. In the present study, we detected that the duck TERT (dTERT) gene was highly expressed in small intestine and kidney, followed by heart, leg muscle, spleen, pancreas, gonad, and liver at neonatal stage. From embryonic to neonatal stage, the highest dTERT mRNA in liver appeared at stage E19 (19 days at embryonic stage), while for the leg muscle the maximum expression occurred at E26. We also measured the relative telomerase activity (RTA) and relative telomere length (RTL) in the examined tissues and found that the changed tendency of RTA and RTL was not very consistent with that of TERT. In silico analysis revealed that there were three CpG islands (S1, S2, and S3) within the 5' regulatory region of the dTERT gene. Bisulfite sequencing PCR (BSP) assay showed that liver (D7, 7 days after birth) which expressed significantly lower dTERT mRNA had an obviously higher methylation level of S1 compared with small intestine (D7) or liver (E19). Quantitative real-time PCR analysis revealed that the expression of DNA methyltransferase DNMT1 in liver (D7) was significantly higher than that in small intestine (D7) or in liver (E19). In vitro, dTERT expression was upregulated and the methylation status of S1 decreased in both duck embryonic fibroblasts and small intestinal epithelial cells following treatment with the demethylation reagent, 5-aza-2'-deoxycytidine (5-aza-dC), further suggesting that dTERT is epigenetically regulated by DNA methylation. This work lays a solid foundation for further study of TERT function and regulation in avian species.
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Affiliation(s)
- Taoyan Yuan
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.,Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, 145 Shiqiao Road, Hangzhou 310021, China
| | - Wanqiu Zhao
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.,Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, 145 Shiqiao Road, Hangzhou 310021, China
| | - Yifan Niu
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan, China
| | - Yan Fu
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China
| | - Lizhi Lu
- Institute of Animal Husbandry and Veterinary Science, Zhejiang Academy of Agricultural Sciences, 145 Shiqiao Road, Hangzhou 310021, China.,Key Laboratory of Information Traceability for Agricultural Products, Ministry of Agriculture of China, Hangzhou 310021, Zhejiang, China
| | - Dong Niu
- College of Animal Science and Technology, Zhejiang A&F University
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21
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X-rays Activate Telomeric Homologous Recombination Mediated Repair in Primary Cells. Cells 2019; 8:cells8070708. [PMID: 31336873 PMCID: PMC6678842 DOI: 10.3390/cells8070708] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/27/2019] [Accepted: 07/06/2019] [Indexed: 12/31/2022] Open
Abstract
Cancer cells need to acquire telomere maintenance mechanisms in order to counteract progressive telomere shortening due to multiple rounds of replication. Most human tumors maintain their telomeres expressing telomerase whereas the remaining 15%–20% utilize the alternative lengthening of telomeres (ALT) pathway. Previous studies have demonstrated that ionizing radiations (IR) are able to modulate telomere lengths and to transiently induce some of the ALT-pathway hallmarks in normal primary fibroblasts. In the present study, we investigated the telomere length modulation kinetics, telomeric DNA damage induction, and the principal hallmarks of ALT over a period of 13 days in X-ray-exposed primary cells. Our results show that X-ray-treated cells primarily display telomere shortening and telomeric damage caused by persistent IR-induced oxidative stress. After initial telomere erosion, we observed a telomere elongation that was associated to the transient activation of a homologous recombination (HR) based mechanism, sharing several features with the ALT pathway observed in cancer cells. Data indicate that telomeric damage activates telomeric HR-mediated repair in primary cells. The characterization of HR-mediated telomere repair in normal cells may contribute to the understanding of the ALT pathway and to the identification of novel strategies in the treatment of ALT-positive cancers.
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Mensà E, Latini S, Ramini D, Storci G, Bonafè M, Olivieri F. The telomere world and aging: Analytical challenges and future perspectives. Ageing Res Rev 2019; 50:27-42. [PMID: 30615937 DOI: 10.1016/j.arr.2019.01.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/15/2018] [Accepted: 01/03/2019] [Indexed: 12/12/2022]
Abstract
Telomeres, the terminal nucleoprotein structures of eukaryotic chromosomes, play pleiotropic functions in cellular and organismal aging. Telomere length (TL) varies throughout life due to the influence of genetic factors and to a complex balancing between "shortening" and "elongation" signals. Telomerase, the only enzyme that can elongate a telomeric DNA chain, and telomeric repeat-containing RNA (TERRA), a long non-coding RNA involved in looping maintenance, play key roles in TL during life. Despite recent advances in the knowledge of TL, TERRA and telomerase activity (TA) biology and their measurement techniques, the experimental and theoretical issues involved raise a number of problems that should carefully be considered by researchers approaching the "telomere world". The increasing use of such parameters - hailed as promising clinically relevant biomarkers - has failed to be paralleled by the development of automated and standardized measurement technology. Consequently, associating given TL values to specific pathological conditions involves on the one hand technological issues and on the other clinical-biological issues related to the planning of clinically relevant association studies. Addressing these issues would help avoid major biases in association studies involving TL and a number of outcomes, especially those focusing on psychological and bio-behavioral variables. The main challenge in telomere research is the development of accurate and reliable measurement methods to achieve simple and sensitive TL, TERRA, and TA detection. The discovery of the localization of telomeres and TERRA in cellular and extracellular compartments had added an additional layer of complexity to the measurement of these age-related biomarkers. Since combined analysis of TL, TERRA and TA may well provide more exhaustive clinical information than a single parameter, we feel it is important for researchers in the various fields to become familiar with their most common measurement techniques and to be aware of the respective merits and drawbacks of these approaches.
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Affiliation(s)
- Emanuela Mensà
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Silvia Latini
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Deborah Ramini
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Gianluca Storci
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy; Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Bologna, Italy
| | - Massimiliano Bonafè
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy; Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Bologna, Italy; Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Biosciences Laboratory, Meldola, Italy
| | - Fabiola Olivieri
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy; Center of Clinical Pathology and Innovative Therapy, IRCCS INRCA, Ancona, Italy.
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23
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Vukašinović AR, Kotur-Stevuljević JM, Mlakar V, Sopić MD, Cvetković ZP, Petković MR, Spasojević-Kalimanovska VV, Bogavac-Stanojević NB, Ostanek B. Telomerase stability and evaluation of real-time telomeric repeat amplification protocol. Scand J Clin Lab Invest 2019; 79:188-193. [PMID: 30767570 DOI: 10.1080/00365513.2019.1576220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Telomerase is RNA directed polymerase which acts as reverse transcriptase based on its own RNA component. It is considered to be involved in the pathology of many diseases and is recognized as a potential biomarker. The aims were to determine the sample storage conditions and the time frame for samples analysis, then to prove reliability of enzyme activity measurement with real-time telomeric repeat amplification protocol (TRAP) and to evaluate the suitable standard samples for telomerase activity measurements. Samples used for stability and freeze-thaw study were peripheral blood leukocytes, obtained from apparently healthy persons, patients with diagnosed cancer and cell lines. Telomerase activity was measured using TRAP method, while standard evaluation was done using nuclear magnetic resonance (NMR) technique. Storage at -20 °C preserved telomerase activity in samples from cancer patients for at least 14 days (21.46 ± 0.135 versus 21.84 ± 0.357, p = .756), while samples obtained from healthy persons should be stored at -80 °C. We observed significant decrease of telomerase activity at freeze thaw cycle 5 in cancer patients' samples (21.46 ± 0.135 versus 23.09 ± 0.316, p < .05), and in healthy persons' ones already at cycle 3 (22.74 ± 0.107 versus 24.85 ± 0.151, p < .05). Telomerase activity from cell lines samples showed overall greater stability regarding the storage period and freeze-thaw cycles and it was considered for standard sample, which was confirmed by NMR analysis. Telomerase enzyme had adequate stability while efficacy, linearity, and reproducibility of TRAP method were acceptable for bio-analytical methods. All this indicated that telomerase could be a reliable biomarker.
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Affiliation(s)
- Aleksandra R Vukašinović
- a Faculty of Pharmacy, Department of Medical Biochemistry , University of Belgrade , Belgrade , Serbia
| | | | - Vid Mlakar
- b Faculty of Pharmacy, Department of Clinical Biochemistry , University of Ljubljana , Ljubljana , Slovenia
| | - Miron D Sopić
- a Faculty of Pharmacy, Department of Medical Biochemistry , University of Belgrade , Belgrade , Serbia
| | - Zorica P Cvetković
- c Department of Haematology , Clinical Hospital Center Zemun , Belgrade , Serbia.,d Faculty of Medicine , University of Belgrade , Belgrade , Serbia
| | - Miloš R Petković
- e Faculty of Pharmacy, Department of Organic Chemistry , University of Belgrade , Belgrade , Serbia
| | | | | | - Barbara Ostanek
- b Faculty of Pharmacy, Department of Clinical Biochemistry , University of Ljubljana , Ljubljana , Slovenia
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24
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Fali T, Papagno L, Bayard C, Mouloud Y, Boddaert J, Sauce D, Appay V. New Insights into Lymphocyte Differentiation and Aging from Telomere Length and Telomerase Activity Measurements. THE JOURNAL OF IMMUNOLOGY 2019; 202:1962-1969. [DOI: 10.4049/jimmunol.1801475] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 01/14/2019] [Indexed: 01/13/2023]
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25
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Wang H, Wang H, Jia Y, Zhang M, Li Z. One-pot detection of telomerase activity with high sensitivity and specificity via RNA FRET probes and RNase H-assisted signal cycling amplification. RSC Adv 2019; 9:14817-14821. [PMID: 35516338 PMCID: PMC9064132 DOI: 10.1039/c9ra01816f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Accepted: 04/28/2019] [Indexed: 11/23/2022] Open
Abstract
Human telomerase is a universal cancer biomarker and a promising anticancer therapeutic target. Sensitive and specific detection of telomerase activity is of great significance for cancer diagnosis and treatment. Up to now, many methods have been established to detect the activity of telomerase, but most of these methods require complex probe design and tedious experimental steps generally including telomere extension reaction, amplification of the extended products and signal detection. Herein, we propose a one-pot method to detect the telomerase activity via RNA FRET probes and RNase H-assisted signal cycling amplification, and the proposed assay can integrate the telomere extension reaction, signal amplification and readout in one step without requirement of amplification of the extended products, which greatly simplifies the experimental design and operation steps. Additionally, the proposed one-pot method has high sensitivity and can unequivocally detect the telomerase activity in as few as 5 cancer cells, which holds great potential in telomerase-related fundamental and clinical studies. A one-pot method is developed for the detection of telomerase activity via RNA FRET probes and RNase H-assisted signal cycling amplification.![]()
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Affiliation(s)
- Honghong Wang
- School of Chemistry and Biology Engineering
- University of Science and Technology Beijing
- Beijing
- P. R. China
| | - Hui Wang
- School of Chemistry and Biology Engineering
- University of Science and Technology Beijing
- Beijing
- P. R. China
| | - Yuting Jia
- School of Chemistry and Biology Engineering
- University of Science and Technology Beijing
- Beijing
- P. R. China
| | - Mai Zhang
- School of Chemistry and Biology Engineering
- University of Science and Technology Beijing
- Beijing
- P. R. China
| | - Zhengping Li
- School of Chemistry and Biology Engineering
- University of Science and Technology Beijing
- Beijing
- P. R. China
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26
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Homology Model and Docking-Based Virtual Screening for Ligands of Human Dyskerin as New Inhibitors of Telomerase for Cancer Treatment. Int J Mol Sci 2018; 19:ijms19103216. [PMID: 30340325 PMCID: PMC6214037 DOI: 10.3390/ijms19103216] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 10/06/2018] [Accepted: 10/08/2018] [Indexed: 01/31/2023] Open
Abstract
Immortality is one of the main features of cancer cells. Tumor cells have an unlimited replicative potential, principally due to the holoenzyme telomerase. Telomerase is composed mainly by dyskerin (DKC1), a catalytic retrotranscriptase (hTERT) and an RNA template (hTR). The aim of this work is to develop new inhibitors of telomerase, selecting the interaction between hTR⁻DKC1 as a target. We designed two models of the human protein DKC1: homology and ab initio. These models were evaluated by different procedures, revealing that the homology model parameters were the most accurate. We selected two hydrophobic pockets contained in the PUA (pseudouridine synthase and archaeosine transglycosylase) domain, using structural and stability analysis. We carried out a docking-based virtual screen on these pockets, using the reported mutation K314 as the center of the docking. The hDKC1 model was tested against a library of 450,000 drug-like molecules. We selected the first 10 molecules that showed the highest affinity values to test their inhibitory activity on the cell line MDA MB 231 (Monroe Dunaway Anderson Metastasis Breast cancer 231), obtaining three compounds that showed inhibitory effect. These results allowed us to validate our design and set the basis to continue with the study of telomerase inhibitors for cancer treatment.
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27
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Chen B, Zhang Y, Yang Y, Chen S, Xu A, Wu L, Xu S. Involvement of telomerase activity inhibition and telomere dysfunction in silver nanoparticles anticancer effects. Nanomedicine (Lond) 2018; 13:2067-2082. [PMID: 30203702 DOI: 10.2217/nnm-2018-0036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
AIM To investigate the possible mechanisms of telomerase and telomere underlying the anticancer effects of silver nanoparticles (AgNPs). MATERIALS & METHODS 25nm polyvinylpyrrolidone-coated AgNPs were used. The telomerase activity and telomere function were evaluated. The anticancer effects of AgNPs were gauged with cell viability assay under different statement of telomerase and telomere. RESULTS & CONCLUSION AgNPs could inhibit telomerase activity and lead to telomere shortening and dysfunction. Overexpression of telomerase attenuated the anticancer activity of AgNPs, whereas downregulation of telomerase activity or dysfunction of the telomere enhanced the cytotoxicity of AgNPs in HeLa cells. Our findings provided strong evidence that the anticancer effects of AgNPs were mediated via interference with the telomerase/telomere.
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Affiliation(s)
- Biao Chen
- School of Environmental Science & Optoelectronic Technology, University of Science & Technology of China, Hefei, Anhui, 230026, PR China.,Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Yajun Zhang
- Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.,Institute of Physical & Information Technology, Anhui University, Hefei, Anhui, 230601, PR China
| | - Yaning Yang
- School of Environmental Science & Optoelectronic Technology, University of Science & Technology of China, Hefei, Anhui, 230026, PR China.,Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Shaopeng Chen
- Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.,Institute of Physical & Information Technology, Anhui University, Hefei, Anhui, 230601, PR China
| | - An Xu
- School of Environmental Science & Optoelectronic Technology, University of Science & Technology of China, Hefei, Anhui, 230026, PR China.,Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.,Institute of Physical & Information Technology, Anhui University, Hefei, Anhui, 230601, PR China
| | - Lijun Wu
- School of Environmental Science & Optoelectronic Technology, University of Science & Technology of China, Hefei, Anhui, 230026, PR China.,Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.,Key Laboratory of Environmental Toxicology & Pollution Control Technology of Anhui Province, Hefei, Anhui, 230031, PR China.,Institute of Physical & Information Technology, Anhui University, Hefei, Anhui, 230601, PR China
| | - Shengmin Xu
- Key Laboratory of High Magnetic Field & Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China.,Key Laboratory of Environmental Toxicology & Pollution Control Technology of Anhui Province, Hefei, Anhui, 230031, PR China
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28
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Fali T, Fabre-Mersseman V, Yamamoto T, Bayard C, Papagno L, Fastenackels S, Zoorab R, Koup RA, Boddaert J, Sauce D, Appay V. Elderly human hematopoietic progenitor cells express cellular senescence markers and are more susceptible to pyroptosis. JCI Insight 2018; 3:95319. [PMID: 29997288 DOI: 10.1172/jci.insight.95319] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 05/31/2018] [Indexed: 01/24/2023] Open
Abstract
The maintenance of effective immunity over time is dependent on the capacity of hematopoietic stem cells (HSCs) to sustain the pool of immunocompetent mature cells. Decline of immune competence with old age may stem from HSC defects, including reduced self-renewal potential and impaired lymphopoiesis, as suggested in murine models. To obtain further insights into aging-related alteration of hematopoiesis, we performed a comprehensive study of blood hematopoietic progenitor cells (HPCs) from older humans. In the elderly, HPCs present active oxidative phosphorylation and are pressed to enter cell cycling. However, p53-p21 and p15 cell senescence pathways, associated with telomerase activity deficiency, strong telomere attrition, and oxidative stress, are engaged, thus limiting cell cycling. Moreover, survival of old HPCs is impacted by pyroptosis, an inflammatory form of programmed cell death. Lastly, telomerase activity deficiency and telomere length attrition of old HPCs may be passed on to progeny cells such as naive T lymphocytes, further highlighting the poor hematopoietic potential of the elderly. This pre-senescent profile is characteristic of the multiple intrinsic and extrinsic factors affecting HPCs in elderly individuals and represents a major obstacle in terms of immune reconstitution and efficacy with advanced age.
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Affiliation(s)
- Tinhinane Fali
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Véronique Fabre-Mersseman
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Takuya Yamamoto
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA.,Laboratory of Immunosenescence, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki-City, Osaka, Japan.,Center for AIDS Research, Kumamoto University, Kumamoto, Japan
| | - Charles Bayard
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Laura Papagno
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Solène Fastenackels
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Rima Zoorab
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Richard A Koup
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Jacques Boddaert
- AP-HP, Hôpital Pitié-Salpêtrière, Service de Gériatrie, Paris, France
| | - Delphine Sauce
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Victor Appay
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,International Research Center of Medical Sciences (IRCMS), Kumamoto University, Kumamoto, Japan
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29
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Solomon P, Dong Y, Dogra S, Gupta R. Interleukin 8 is a biomarker of telomerase inhibition in cancer cells. BMC Cancer 2018; 18:730. [PMID: 29986697 PMCID: PMC6038317 DOI: 10.1186/s12885-018-4633-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/25/2018] [Indexed: 12/29/2022] Open
Abstract
Background Telomerase activity is required for both initiation and maintenance of tumorigenesis and over 90% cancers overexpress telomerase. Therefore, telomerase targeting has emerged as a potential strategy for cancer treatment. In agreement with this, several telomerase inhibitors are being tested for cancer treatment and have shown some promise. However, because of the variability in response between the cancer patients, it is important to identify biomarkers that allow for distinguishing cancers that are responsive to telomerase inhibition from the cancers that are not. Therefore, in this study we performed experiments to identify a biomarker that can be used to predict telomerase inhibition induced tumor growth inhibition. Methods In our study, we have performed transcriptome-wide gene expression analysis on multiple ovarian and colon cancer cell lines that were treated with telomerase inhibitor imetelstat and were responsive to telomerase inhibition-induced tumor growth attenuation. Results We demonstrate that telomerase inhibition by telomerase inhibitor imetelstat results in decreased expression of interleukin 8 (IL8) in all telomerase responsive cancer cell lines. This phenomenon is of general occurrence because we find that multiple ovarian and colon cell lines show decrease in IL8 mRNA and protein levels after telomerase inhibition. Additionally, we find loss of IL8 phenocopy Telomerase inhibition mediated growth inhibitory effect in cancer cells. Conclusion Taken together, our results show that IL8 is a biomarker that predict telomerase inhibition mediated growth attenuation of cancer cells and its loss phenocopy telomerase inhibition. Therefore, IL8 expression can be utilized as a biomarker for telomerase targeted cancer therapies to potentially predict therapeutic response. Electronic supplementary material The online version of this article (10.1186/s12885-018-4633-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Peter Solomon
- Department of Pathology, Yale University School of Medicine, LH-306, New Haven, CT, 06510, USA
| | - Yuying Dong
- Department of Pathology, Yale University School of Medicine, LH-306, New Haven, CT, 06510, USA
| | - Shaillay Dogra
- Singapore Institute of Clinical Sciences, Agency for Science Technology and Research (A*STAR), Brenner Centre for Molecular Medicine, 30 Medical Dr., Singapore, 117609, Singapore
| | - Romi Gupta
- Department of Pathology, Yale University School of Medicine, LH-306, New Haven, CT, 06510, USA.
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30
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Ahmed W, Lingner J. PRDX1 and MTH1 cooperate to prevent ROS-mediated inhibition of telomerase. Genes Dev 2018; 32:658-669. [PMID: 29773556 PMCID: PMC6004070 DOI: 10.1101/gad.313460.118] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/23/2018] [Indexed: 11/29/2022]
Abstract
In this study, Ahmed et al. demonstrate that oxidative damage of telomeres inhibits telomerase activity at chromosome ends in cancer cells. Deletion of two antioxidant enzymes—PRDX1 and MTH1, needed for protecting telomeres from oxidative damage—results in loss of telomeric DNA in an oxygen concentration-dependent manner due to inhibition of telomerase, thus providing new insights into the role of antioxidant systems that are required to protect telomeres from oxidation. Telomerase counteracts telomere shortening and cellular senescence in germ, stem, and cancer cells by adding repetitive DNA sequences to the ends of chromosomes. Telomeres are susceptible to damage by reactive oxygen species (ROS), but the consequences of oxidation of telomeres on telomere length and the mechanisms that protect from ROS-mediated telomere damage are not well understood. In particular, 8-oxoguanine nucleotides at 3′ ends of telomeric substrates inhibit telomerase in vitro, whereas, at internal positions, they suppress G-quadruplex formation and were therefore proposed to promote telomerase activity. Here, we disrupt the peroxiredoxin 1 (PRDX1) and 7,8-dihydro-8-oxoguanine triphosphatase (MTH1) genes in cancer cells and demonstrate that PRDX1 and MTH1 cooperate to prevent accumulation of oxidized guanine in the genome. Concomitant disruption of PRDX1 and MTH1 leads to ROS concentration-dependent continuous shortening of telomeres, which is due to efficient inhibition of telomere extension by telomerase. Our results identify antioxidant systems that are required to protect telomeres from oxidation and are necessary to allow telomere maintenance by telomerase conferring immortality to cancer cells.
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Affiliation(s)
- Wareed Ahmed
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Joachim Lingner
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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31
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El Hajj J, Nguyen E, Liu Q, Bouyer C, Adriaenssens E, Hilal G, Ségal-Bendirdjian E. Telomerase regulation by the long non-coding RNA H19 in human acute promyelocytic leukemia cells. Mol Cancer 2018; 17:85. [PMID: 29703210 PMCID: PMC5923027 DOI: 10.1186/s12943-018-0835-8] [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] [Received: 12/28/2017] [Accepted: 04/16/2018] [Indexed: 01/06/2023] Open
Abstract
Background Since tumor growth requires reactivation of telomerase (hTERT), this enzyme is a challenging target for drug development. Therefore, it is of great interest to identify telomerase expression and activity regulators. Retinoids are well-known inducers of granulocytic maturation associated with hTERT repression in acute promyelocytic leukemia (APL) blasts. In a maturation-resistant APL cell line, we have previously identified a new pathway of retinoid-induced hTERT transcriptional repression independent of differentiation. Furthermore, we reported the isolation of a cell variant resistant to this repression. Those cell lines could serve as unique tools to identify new telomerase regulators. Methods Using a microarray approach we identified the long non-coding RNA, H19 as a potential candidate playing a role in telomerase regulation. Expression of H19, hTERT, and hTR were examined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Telomerase activity was quantified by quantitative telomeric repeats amplification protocol (qTRAP). In vitro and in vivo assays were performed to investigate H19 function on telomerase expression and activity. Results We showed both in retinoid-treated cell lines and in APL patient cells an inverse relationship between the expression of H19 and the expression and activity of hTERT. Exploring the mechanistic link between H19 and hTERT regulation, we showed that H19 is able to impede telomerase function by disruption of the hTERT-hTR interaction. Conclusions This study identifies a new way of telomerase regulation through H19’s involvement and thereby reveals a new function for this long non-coding RNA that can be targeted for therapeutic purpose. Electronic supplementary material The online version of this article (10.1186/s12943-018-0835-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joëlle El Hajj
- INSERM UMR-S 1007, Cellular Homeostasis and Cancer, Paris, France.,Paris-Descartes University, Paris Sorbonne Cité, Paris, France.,Paris-Sud University, Paris-Saclay University, Orsay, France.,Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Eric Nguyen
- INSERM UMR-S 1007, Cellular Homeostasis and Cancer, Paris, France.,Paris-Descartes University, Paris Sorbonne Cité, Paris, France
| | - Qingyuan Liu
- INSERM UMR-S 1007, Cellular Homeostasis and Cancer, Paris, France.,Paris-Descartes University, Paris Sorbonne Cité, Paris, France.,Present address: Bristol-Myers Squibb (China) Investment Co. Ltd., Shanghai, 200040, People's Republic of China
| | - Claire Bouyer
- INSERM UMR-S 1007, Cellular Homeostasis and Cancer, Paris, France.,Paris-Descartes University, Paris Sorbonne Cité, Paris, France
| | | | - George Hilal
- Cancer and Metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon
| | - Evelyne Ségal-Bendirdjian
- INSERM UMR-S 1007, Cellular Homeostasis and Cancer, Paris, France. .,Paris-Descartes University, Paris Sorbonne Cité, Paris, France. .,Paris-Sud University, Paris-Saclay University, Orsay, France. .,INSERM UMR-S 1007, Paris-Descartes University, 45 rue des Saints-Pères, 75006, Paris, France.
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32
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Comprehensive analysis of telomerase inhibition by gallotannin. Oncotarget 2018; 9:18712-18719. [PMID: 29721155 PMCID: PMC5922349 DOI: 10.18632/oncotarget.24642] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 02/24/2018] [Indexed: 11/25/2022] Open
Abstract
Gallotannin (or tannic acid) is a naturally occurring compound that inhibits cell growth and activity of different DNA-polymerases, including telomerase. The purpose of the present study was to gain insight into the mechanism of telomerase inhibition by gallotannin. We determined that gallotannin inhibits telomerase in vitro with an half maximal inhibitory concentrations value of 130 nM, but it does not affect telomerase complex assembly and component levels in vivo. The inhibitory activity of gallotannin against telomerase provides an additional explanation for the anti-cancer activities of this compound.
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33
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Kras mutations increase telomerase activity and targeting telomerase is a promising therapeutic strategy for Kras-mutant NSCLC. Oncotarget 2018; 8:179-190. [PMID: 27329725 PMCID: PMC5352098 DOI: 10.18632/oncotarget.10162] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 06/06/2016] [Indexed: 01/14/2023] Open
Abstract
As shortened telomeres inhibit tumor formation and prolong life span in a KrasG12D mouse lung cancer model, we investigated the implications of telomerase in Kras-mutant NSCLC. We found that Kras mutations increased TERT (telomerase reverse transcriptase) mRNA expression and telomerase activity and telomere length in both immortalized bronchial epithelial cells (BEAS-2B) and lung adenocarcinoma cells (Calu-3). MEK inhibition led to reduced TERT expression and telomerase activity. Furthermore, telomerase inhibitor BIBR1532 shortened telomere length and inhibited mutant Kras-induced long-term proliferation, colony formation and migration capabilities of BEAS-2B and Calu-3 cells. Importantly, BIBR1532 sensitized oncogenic Kras expressing Calu-3 cells to chemotherapeutic agents. The Calu-3-KrasG12D xenograft mouse model confirmed that BIBR1532 enhanced the antitumor efficacy of paclitaxel in vivo. In addition, higher TERT expression was seen in Kras-mutant NSCLC than that with wild-type Kras. Our data suggest that Kras mutations increase telomerase activity and telomere length by activating the RAS/MEK pathway, which contributes to an aggressive phenotype of NSCLC. Kras mutations-induced lung tumorigenesis and chemoresistance are attenuated by telomerase inhibition. Targeting telomerase/telomere may be a promising therapeutic strategy for patients with Kras-mutant NSCLC.
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Yan T, Ooi WF, Qamra A, Cheung A, Ma D, Sundaram GM, Xu C, Xing M, Poon L, Wang J, Loh YP, Ho JHJ, Ng JJQ, Ramlee MK, Aswad L, Rozen SG, Ghosh S, Bard FA, Sampath P, Tergaonkar V, Davies JOJ, Hughes JR, Goh E, Bi X, Fullwood MJ, Tan P, Li S. HoxC5 and miR-615-3p target newly evolved genomic regions to repress hTERT and inhibit tumorigenesis. Nat Commun 2018; 9:100. [PMID: 29311615 PMCID: PMC5758779 DOI: 10.1038/s41467-017-02601-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 12/13/2017] [Indexed: 02/06/2023] Open
Abstract
The repression of telomerase activity during cellular differentiation promotes replicative aging and functions as a physiological barrier for tumorigenesis in long-lived mammals, including humans. However, the underlying mechanisms remain largely unclear. Here we describe how miR-615-3p represses hTERT expression. mir-615-3p is located in an intron of the HOXC5 gene, a member of the highly conserved homeobox family of transcription factors controlling embryogenesis and development. Unexpectedly, we found that HoxC5 also represses hTERT expression by disrupting the long-range interaction between hTERT promoter and its distal enhancer. The 3'UTR of hTERT and its upstream enhancer region are well conserved in long-lived primates. Both mir-615-3p and HOXC5 are activated upon differentiation, which constitute a feed-forward loop that coordinates transcriptional and post-transcriptional repression of hTERT during cellular differentiation. Deregulation of HOXC5 and mir-615-3p expression may contribute to the activation of hTERT in human cancers.
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Affiliation(s)
- TingDong Yan
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Wen Fong Ooi
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672, Singapore
| | - Aditi Qamra
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 2 Medical Drive, Singapore, 117597, Singapore
| | - Alice Cheung
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - DongLiang Ma
- Neuroscience Academic Clinical Programme, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Department of Research, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
| | | | - Chang Xu
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Singapore
| | - Manjie Xing
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672, Singapore
| | - LaiFong Poon
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Jing Wang
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Yan Ping Loh
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Jess Hui Jie Ho
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Joscelyn Jun Quan Ng
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Muhammad Khairul Ramlee
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Luay Aswad
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Steve G Rozen
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Duke-NUS Centre for Computational Biology, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Sujoy Ghosh
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
| | - Frederic A Bard
- Institute of Molecular and Cell Biology (IMCB), Singapore, 138673, Singapore
| | - Prabha Sampath
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Institute of Medical Biology (IMB), 8A Biomedical Grove, Singapore, 138648, Singapore
| | - Vinay Tergaonkar
- Institute of Molecular and Cell Biology (IMCB), Singapore, 138673, Singapore
| | - James O J Davies
- Medical Research Council (MRC) Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, Oxford University, Oxford, OX3 9DS, UK
| | - Jim R Hughes
- Medical Research Council (MRC) Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, Oxford University, Oxford, OX3 9DS, UK
| | - Eyleen Goh
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 2 Medical Drive, Singapore, 117597, Singapore
- Neuroscience Academic Clinical Programme, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Department of Research, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore
| | - Xuezhi Bi
- Bioprocessing Technology Institute, 20 Biopolis Street, Singapore, 138669, Singapore
| | - Melissa Jane Fullwood
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
- Institute of Molecular and Cell Biology (IMCB), Singapore, 138673, Singapore
| | - Patrick Tan
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 2 Medical Drive, Singapore, 117597, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Singapore
- Duke-NUS Centre for Computational Biology, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore
- Cellular and Molecular Research, National Cancer Centre, 11 Hospital Drive, Singapore, 169610, Singapore
| | - Shang Li
- Cancer and Stem Cell Biology Program, Duke-NUS Medical School, 8 College Road, Singapore, 169857, Singapore.
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 2 Medical Drive, Singapore, 117597, Singapore.
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Wege H, Chui MS, Le HT, Strom SC, Zern MA. In Vitro Expansion of Human Hepatocytes is Restricted by Telomere-Dependent Replicative Aging. Cell Transplant 2017; 12:897-906. [PMID: 14763510 DOI: 10.3727/000000003771000138] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Currently, different techniques to expand human hepatocytes in vitro are being investigated to generate enough cells for liver-directed cell therapies. However, based on observations in fibroblasts and other cell types, telomere attrition limits the proliferative capacity of normal somatic cells. Therefore, we explored whether telomere-dependent replicative aging restricts the in vitro proliferation of human hepatocytes. Subpopulations of cells isolated from a neonatal liver and characterized as hepatocyte derived by RT-PCR and flow cytometry started to proliferate 5–7 days after plating and were termed proliferating human hepatocytes (PHH). Following retroviral-mediated transduction of the catalytic telomerase subunit, telomerase reverse transcriptase (hTERT), telomerase activity increased from almost undetectable levels to levels as high as in HepG2 and other telomerase-positive cell lines. As expected, untransduced PHH progressively lost telomeric repeats and arrested after 30–35 cell divisions with telomeres of less than 5 kilo bases. In comparison, telomerase-reconstituted PHH maintained elongated telomeres and continued to proliferate as shown by colorimetric assays and cell counts. In this study, telomere stabilization extended the proliferative capacity of in vitro proliferating human neonatal hepatocytes. Therefore, telomere attrition needs to be addressed when developing techniques to expand human hepatocytes.
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Affiliation(s)
- Henning Wege
- Transplant Research Institute, University of California, Davis Medical Center, Sacramento, CA 95817, USA
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Coluzzi E, Buonsante R, Leone S, Asmar AJ, Miller KL, Cimini D, Sgura A. Transient ALT activation protects human primary cells from chromosome instability induced by low chronic oxidative stress. Sci Rep 2017; 7:43309. [PMID: 28240303 PMCID: PMC5327399 DOI: 10.1038/srep43309] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 01/25/2017] [Indexed: 12/22/2022] Open
Abstract
Cells are often subjected to the effect of reactive oxygen species (ROS) as a result of both intracellular metabolism and exposure to exogenous factors. ROS-dependent oxidative stress can induce 8-oxodG within the GGG triplet found in the G-rich human telomeric sequence (TTAGGG), making telomeres highly susceptible to ROS-induced oxidative damage. Telomeres are nucleoprotein complexes that protect the ends of linear chromosomes and their dysfunction is believed to affect a wide range of cellular and/or organismal processes. Acute oxidative stress was shown to affect telomere integrity, but how prolonged low level oxidative stress, which may be more physiologically relevant, affects telomeres is still poorly investigated. Here, we explored this issue by chronically exposing human primary fibroblasts to a low dose of hydrogen peroxide. We observed fluctuating changes in telomere length and fluctuations in the rates of chromosome instability phenotypes, such that when telomeres shortened, chromosome instability increased and when telomeres lengthened, chromosome instability decreased. We found that telomere length fluctuation is associated with transient activation of an alternative lengthening of telomere (ALT) pathway, but found no evidence of cell death, impaired proliferation, or cell cycle arrest, suggesting that ALT activation may prevent oxidative damage from reaching levels that threaten cell survival.
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Affiliation(s)
- Elisa Coluzzi
- Department of Science, University Roma Tre, V. le G. Marconi, 446, 00146, Rome, Italy
| | - Rossella Buonsante
- Department of Science, University Roma Tre, V. le G. Marconi, 446, 00146, Rome, Italy
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Stefano Leone
- Department of Science, University Roma Tre, V. le G. Marconi, 446, 00146, Rome, Italy
| | - Anthony J. Asmar
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Kelley L. Miller
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Daniela Cimini
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
- Biocomplexity Institute, Virginia Tech, 1015 Life Science Circle, Blacksburg, VA, 24061, USA
| | - Antonella Sgura
- Department of Science, University Roma Tre, V. le G. Marconi, 446, 00146, Rome, Italy
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Xu X, Wei M, Liu Y, Liu X, Wei W, Zhang Y, Liu S. A simple, fast, label-free colorimetric method for detection of telomerase activity in urine by using hemin-graphene conjugates. Biosens Bioelectron 2017; 87:600-606. [DOI: 10.1016/j.bios.2016.09.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/23/2016] [Accepted: 09/01/2016] [Indexed: 12/18/2022]
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Ahmed R, Roger L, Costa Del Amo P, Miners KL, Jones RE, Boelen L, Fali T, Elemans M, Zhang Y, Appay V, Baird DM, Asquith B, Price DA, Macallan DC, Ladell K. Human Stem Cell-like Memory T Cells Are Maintained in a State of Dynamic Flux. Cell Rep 2016; 17:2811-2818. [PMID: 27974195 PMCID: PMC5186732 DOI: 10.1016/j.celrep.2016.11.037] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 09/23/2016] [Accepted: 11/10/2016] [Indexed: 11/29/2022] Open
Abstract
Adaptive immunity requires the generation of memory T cells from naive precursors selected in the thymus. The key intermediaries in this process are stem cell-like memory T (TSCM) cells, multipotent progenitors that can both self-renew and replenish more differentiated subsets of memory T cells. In theory, antigen specificity within the TSCM pool may be imprinted statically as a function of largely dormant cells and/or retained dynamically by more transitory subpopulations. To explore the origins of immunological memory, we measured the turnover of TSCM cells in vivo using stable isotope labeling with heavy water. The data indicate that TSCM cells in both young and elderly subjects are maintained by ongoing proliferation. In line with this finding, TSCM cells displayed limited telomere length erosion coupled with high expression levels of active telomerase and Ki67. Collectively, these observations show that TSCM cells exist in a state of perpetual flux throughout the human lifespan.
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Affiliation(s)
- Raya Ahmed
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK
| | - Laureline Roger
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Pedro Costa Del Amo
- Department of Medicine, St. Mary's Hospital, Imperial College London, London W2 1PG, UK
| | - Kelly L Miners
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Rhiannon E Jones
- Division of Cancer and Genetics, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Lies Boelen
- Department of Medicine, St. Mary's Hospital, Imperial College London, London W2 1PG, UK
| | - Tinhinane Fali
- Sorbonne Universités, UPMC Université Paris 06, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 75013 Paris, France; INSERM U1135, CIMI-Paris, 75013 Paris, France
| | - Marjet Elemans
- Department of Medicine, St. Mary's Hospital, Imperial College London, London W2 1PG, UK
| | - Yan Zhang
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK
| | - Victor Appay
- Sorbonne Universités, UPMC Université Paris 06, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 75013 Paris, France; INSERM U1135, CIMI-Paris, 75013 Paris, France
| | - Duncan M Baird
- Division of Cancer and Genetics, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK
| | - Becca Asquith
- Department of Medicine, St. Mary's Hospital, Imperial College London, London W2 1PG, UK
| | - David A Price
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK; Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Derek C Macallan
- Institute for Infection and Immunity, St. George's, University of London, London SW17 0RE, UK; St. George's University Hospitals National Health Service Foundation Trust, Blackshaw Road, London SW17 0QT, UK.
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK.
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Goh YY, Yan YK, Tan NS, Goh SA, Li S, Teoh YC, Lee PPF. Downregulation of oncogenic RAS and c-Myc expression in MOLT-4 leukaemia cells by a salicylaldehyde semicarbazone copper(II) complex. Sci Rep 2016; 6:36868. [PMID: 27841290 PMCID: PMC5107956 DOI: 10.1038/srep36868] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 10/21/2016] [Indexed: 12/19/2022] Open
Abstract
Copper complexes with potent anti-tumor effect have been extensively developed. Most investigations of their modes of action focused on the biomolecular targets but not the signal transduction between target binding and cell death. We have previously shown that the cytotoxic complex pyridine(2,4-dihydroxybenzaldehyde dibenzyl semicarbazone)copper(II) (complex 1) shows selective binding to human telomeric G-quadruplex DNA over double-stranded DNA in vitro. Herein, we elucidate the mechanism of action by which complex 1 induces apoptosis in MOLT-4 cells. Complex 1 accumulates in the nuclei and differentially downregulates the expression of c-Myc, c-Kit and KRAS oncogenes. Chemical affinity capture assay results show that the complex is associated with c-Myc and KRAS quadruplex sequences in MOLT-4 cells. We further showed that the reduction in Ras protein expression resulted in attenuated MEK-ERK and PI3K-Akt signalling activities, leading to the activation of caspase-dependent apoptosis. Notably, complex 1 increased the sensitivity of MOLT-4 cells to cisplatin and vice versa. Overall, we demonstrated that complex 1 induces apoptosis, at least in part, by suppressing KRAS, c-Kit and c-Myc oncogene expression and the pro-survival MEK-ERK and PI3K-Akt signalling pathways.
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Affiliation(s)
- Yan-Yih Goh
- Natural Sciences &Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore
| | - Yaw-Kai Yan
- Natural Sciences &Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore
| | - Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.,Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.,Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore.,KK Women's and Children's Hospital, 100 Bukit Timah Road, Singapore 229899, Singapore
| | - Su-Ann Goh
- Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
| | - Shang Li
- Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
| | - You-Chuan Teoh
- Natural Sciences &Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore
| | - Peter P F Lee
- Singapore Institute of Technology, 10 Dover Drive, Singapore 138683, Singapore
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Telomere Transcripts Target Telomerase in Human Cancer Cells. Genes (Basel) 2016; 7:genes7080046. [PMID: 27537914 PMCID: PMC4999834 DOI: 10.3390/genes7080046] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/24/2016] [Accepted: 07/29/2016] [Indexed: 12/14/2022] Open
Abstract
Long non-coding transcripts from telomeres, called telomeric repeat-containing RNA (TERRA), were identified as blocking telomerase activity (TA), a telomere maintenance mechanism (TMM), in tumors. We expressed recombinant TERRA transcripts in tumor cell lines with TA and with alternative lengthening of telomeres (ALT) to study effects on TMM and cell growth. Adeno- and lentivirus constructs (AV and LV) were established for transient and stable expression of approximately 130 units of telomere hexanucleotide repeats under control of cytomegalovirus (CMV) and human RNase P RNA H1 (hH1) promoters with and without polyadenylation, respectively. Six human tumor cell lines either using telomerase or ALT were infected and analyzed for TA levels. Pre-infection cells using telomerase had 1%-3% of the TERRA expression levels of ALT cells. AV and LV expression of recombinant TERRA in telomerase positive cells showed a 1.3-2.6 fold increase in TERRA levels, and a decrease in TA of 25%-58%. Dominant-negative or small hairpin RNA (shRNA) viral expression against human telomerase reverse transcriptase (hTERT) results in senescence, not induced by TERRA expression. Population doubling time, cell viability and TL (telomere length) were not impacted by ectopic TERRA expression. Clonal growth was reduced by TERRA expression in TA but not ALT cell lines. ALT cells were not affected by treatments applied. Established cell models and tools may be used to better understand the role of TERRA in the cell, especially for targeting telomerase.
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Hata T, Dal Molin M, Suenaga M, Yu J, Pittman M, Weiss M, Canto MI, Wolfgang C, Lennon AM, Hruban RH, Goggins M. Cyst Fluid Telomerase Activity Predicts the Histologic Grade of Cystic Neoplasms of the Pancreas. Clin Cancer Res 2016; 22:5141-5151. [PMID: 27230749 DOI: 10.1158/1078-0432.ccr-16-0311] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 05/10/2016] [Indexed: 12/25/2022]
Abstract
PURPOSE Pancreatic cysts frequently pose clinical dilemmas. On one hand, cysts with high-grade dysplasia offer opportunities for cure, on the other hand, those with low-grade dysplasia are easily over treated. Cyst fluid markers have the potential to improve the evaluation of these cysts. Because telomerase activity is commonly activated in malignant cells, we evaluated the diagnostic performance of cyst fluid telomerase activity measurements for predicting histologic grade. EXPERIMENTAL DESIGN Telomerase activity was measured using telomerase repeat amplification with digital-droplet PCR in surgically aspirated cyst fluid samples from 219 patients who underwent pancreatic resection for a cystic lesion (184 discovery, 35 validation) and 36 patients who underwent endoscopic ultrasound fine-needle aspiration. Methodologic and clinical factors associated with telomerase activity were examined. RESULTS Telomerase activity was reduced in samples that had undergone prior thawing. Among 119 samples not previously thawed, surgical cyst fluids from cystic neoplasms with high-grade dysplasia ± associated invasive cancer had higher telomerase activity [median (interquartile range), 1,158 (295.9-13,033)] copies/μL of cyst fluid than those without [19.74 (2.58-233.6) copies/μL; P < 0.001)]. Elevated cyst fluid telomerase activity had a diagnostic accuracy for invasive cancer/high-grade dysplasia of 88.1% (discovery), 88.6% (validation), and 88.2% (merged). Among cysts classified preoperatively as having "worrisome features," cyst fluid telomerase activity had high diagnostic performance (sensitivity 73.7%, specificity 90.6%, accuracy, 86.1%). In multivariate analysis, telomerase activity independently predicted the presence of invasive cancer/high-grade dysplasia. CONCLUSIONS Cyst fluid telomerase activity can be a useful predictor of the neoplastic grade of pancreatic cysts. Clin Cancer Res; 22(20); 5141-51. ©2016 AACRSee related commentary by Allen et al., p. 4966.
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Affiliation(s)
- Tatsuo Hata
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Marco Dal Molin
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Masaya Suenaga
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Jun Yu
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Meredith Pittman
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Matthew Weiss
- Department of Surgery, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Marcia I Canto
- Department of Surgery, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Medicine, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Christopher Wolfgang
- Department of Surgery, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Anne Marie Lennon
- Department of Surgery, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Medicine, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Ralph H Hruban
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Michael Goggins
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Medicine, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins Medical Institutions, Baltimore, Maryland.
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Wang H, Wang H, Liu C, Duan X, Li Z. Ultrasensitive detection of telomerase activity in a single cell using stem-loop primer-mediated exponential amplification (SPEA) with near zero nonspecific signal. Chem Sci 2016; 7:4945-4950. [PMID: 30155143 PMCID: PMC6018513 DOI: 10.1039/c6sc00802j] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 04/28/2016] [Indexed: 12/12/2022] Open
Abstract
A SPEA strategy is developed for the detection of telomerase activity in a single cell with a near zero nonspecific signal.
Telomerase is a crucial biomarker for cancers. Its reliable and sensitive detection, particularly in a single cell, has great significance for the early diagnosis of cancers, studies on tumor progression and anticancer therapy, which remain a challenge, due to nonspecific amplification. Herein, we developed a novel stem-loop primer-mediated exponential amplification (SPEA) strategy, which can specifically and efficiently amplify the telomerase-elongated telomere repeat unit with near zero nonspecific signal. The SPEA-based assay can accurately detect telomerase activity in the crude lysate of a single cell and is suited for detecting the cellular heterogeneity arising from cell-to-cell variations.
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Affiliation(s)
- Honghong Wang
- Key Laboratory of Applied Surface and Colloid Chemistry , Ministry of Education , Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province , School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710062 , Shaanxi Province , P. R. China . ;
| | - Hui Wang
- Key Laboratory of Applied Surface and Colloid Chemistry , Ministry of Education , Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province , School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710062 , Shaanxi Province , P. R. China . ;
| | - Chenghui Liu
- Key Laboratory of Applied Surface and Colloid Chemistry , Ministry of Education , Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province , School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710062 , Shaanxi Province , P. R. China . ;
| | - Xinrui Duan
- Key Laboratory of Applied Surface and Colloid Chemistry , Ministry of Education , Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province , School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710062 , Shaanxi Province , P. R. China . ;
| | - Zhengping Li
- Key Laboratory of Applied Surface and Colloid Chemistry , Ministry of Education , Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province , School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710062 , Shaanxi Province , P. R. China . ;
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Lin Y, Yang L, Yue G, Chen L, Qiu B, Guo L, Lin Z, Chen G. Label-free electrochemiluminescence biosensor for ultrasensitive detection of telomerase activity in HeLa cells based on extension reaction and intercalation of Ru(phen)3 2+. Anal Bioanal Chem 2016; 408:7105-11. [DOI: 10.1007/s00216-016-9561-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/31/2016] [Accepted: 04/12/2016] [Indexed: 11/30/2022]
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Suryo Rahmanto Y, Jung JG, Wu RC, Kobayashi Y, Heaphy CM, Meeker AK, Wang TL, Shih IM. Inactivating ARID1A Tumor Suppressor Enhances TERT Transcription and Maintains Telomere Length in Cancer Cells. J Biol Chem 2016; 291:9690-9. [PMID: 26953344 DOI: 10.1074/jbc.m115.707612] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Indexed: 12/26/2022] Open
Abstract
ARID1A is a tumor suppressor gene that belongs to the switch/sucrose non-fermentable chromatin remodeling gene family. It is mutated in many types of human cancer with the highest frequency in endometrium-related ovarian and uterine neoplasms including ovarian clear cell, ovarian endometrioid, and uterine endometrioid carcinomas. We have previously reported that mutations in the promoter of human telomerase reverse transcriptase (TERT) rarely co-occur with the loss of ARID1A protein expression, suggesting a potential role of ARID1A in telomere biology. In this study, we demonstrate that ARID1A negatively regulates TERT transcriptional regulation and activity via binding to the regulatory element of TERT and promotes a repressive histone mode. Induction of ARID1A expression was associated with increased occupancy of SIN3A and H3K9me3, known transcription repressor and histone repressor marks, respectively. Thus, loss of ARID1A protein expression caused by inactivating mutations reactivates TERT transcriptional activity and confers a survival advantage of tumor cells by maintaining their telomeres.
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Affiliation(s)
- Yohan Suryo Rahmanto
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and
| | - Jin-Gyoung Jung
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and
| | - Ren-Chin Wu
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and the Department of Pathology, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan 333, Taiwan, and
| | - Yusuke Kobayashi
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and the Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Christopher M Heaphy
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and
| | - Alan K Meeker
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and
| | - Tian-Li Wang
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and the Department of Gynecology/Obstetrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231
| | - Ie-Ming Shih
- From the Department of Pathology, the Sidney Kimmel Comprehensive Cancer Center, and the Department of Gynecology/Obstetrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231,
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Xin X, Senthilkumar PK, Schnoor JL, Ludewig G. Effects of PCB126 and PCB153 on telomerase activity and telomere length in undifferentiated and differentiated HL-60 cells. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:2173-85. [PMID: 26330309 PMCID: PMC4718801 DOI: 10.1007/s11356-015-5187-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 08/10/2015] [Indexed: 05/08/2023]
Abstract
PCBs are persistent organic pollutants that are carcinogenic and immunotoxic and have developmental toxicity. This suggests that they may interfere with normal cell maturation. Cancer and stem/progenitor cells have telomerase activity to maintain and protect the chromosome ends, but lose this activity during differentiation. We hypothesized that PCBs interfere with telomerase activity and the telomere complex, thereby disturbing cell differentiation and stem/progenitor cell function. HL-60 cells are cancer cells that can differentiated into granulocytes and monocytes. We exposed HL-60 cells to PCB126 (dioxin-like) and PCB153 (nondioxin-like) 6 days before and during 3 days of differentiation. The differentiated cells showed G0/G1 phase arrest and very low telomerase activity. hTERT and hTR, two telomerase-related genes, were downregulated. The telomere shelterins TRF1, TRF2, and POT1 were upregulated in granulocytes, and TRF2 was upregulated and POT1 downregulated in monocytes. Both PCBs further reduced telomerase activity in differentiated cells, but had only small effects on the differentiation and telomere-related genes. Treatment of undifferentiated HL-60 cells for 30 days with PCB126 produced a downregulation of telomerase activity and a decrease of hTERT, hTR, TRF1, and POT1 gene expression. With PCB153, the effects were less pronounced and some shelterin genes were increased after 30 days of exposure. With each PCB, no differentiation of cells was observed and cells continued to proliferate despite reduced telomerase activity, resulting in shortened telomeres after 30 days of exposure. These results indicate cell-type and PCB congener-specific effects on telomere/telomerase-related genes. Although PCBs do not seem to strongly affect differentiation, they may influence stem or progenitor cells through telomere attrition with potential long-term consequences for health.
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Affiliation(s)
- Xing Xin
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
| | - P K Senthilkumar
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
- Risk Evaluation Branch, Center for Disease Control and Prevention, Cincinnati, OH, 45226, USA
| | - Jerald L Schnoor
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Occupational and Environmental Health, The University of Iowa, 100 Oakdale Campus, IREH, Iowa City, IA, 52242-5000, USA
| | - Gabriele Ludewig
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA.
- Department of Occupational and Environmental Health, The University of Iowa, 100 Oakdale Campus, IREH, Iowa City, IA, 52242-5000, USA.
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46
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Deng W, Cheung ST, Tsao SW, Wang XM, Tiwari AFY. Telomerase activity and its association with psychological stress, mental disorders, lifestyle factors and interventions: A systematic review. Psychoneuroendocrinology 2016; 64:150-63. [PMID: 26677763 DOI: 10.1016/j.psyneuen.2015.11.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/30/2015] [Accepted: 11/20/2015] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To summarise and discuss the association between telomerase activity and psychological stress, mental disorders and lifestyle factors. METHOD A systematic review was carried out to identify prospective or retrospective studies and interventions published up to June 2015 that reported associations between telomerase activity and psychological stress, mental disorders and lifestyle factors. Electronic data bases of PubMed, ProQuest, CINAHL and Google Scholar were searched. RESULTS Twenty six studies on humans measured telomerase activity in peripheral blood mononuclear cells (PBMCs) or leukocytes and examined its association with psychological stress, mental disorders and lifestyle factors. Of those studies, three reported significantly decreased telomerase activity in individuals under chronic psychological stress. Interestingly, one of the three studies found that acute laboratory psychological stress significantly increased telomerase activity. Nine studies reported mixed results on association between mental disorders and telomerase activity. Of the nine studies, five reported that major depressive disorder (MDD) was associated with significantly increased telomerase activity. In thirteen out of fourteen studies on lifestyle factors, it was reported that physical exercise, diet micronutrient supplementation, mindfulness meditation, Qigong practice or yoga mediation resulted in increase in telomerase activity. In addition, two studies on animal models showed that depression-like behaviour was associated with decreased hippocampus telomerase activity. Five animal studies showed that physical exercise increased telomerase activity by cell-type-specific and genotype-specific manners. CONCLUSION Although multi-facet results were reported on the association between telomerase activity and psychological stress, mental disorders and lifestyle factors, there were some consistent findings in humans such as (1) decreased telomerase activity in individuals under chronic stress, (2) increased telomerase activity in individuals with MDD, and (3) increased telomerase activity in individuals under lifestyle interventions. Animal studies showed that physical exercise increased telomerase activity in specific cell-types. However, the exact mechanisms for the changes in telomerase activity have not been elucidated. We propose conglomerate models connecting chronic psychological stress, depression, mediation and physical exercise to telomerase activation. Several areas for future research are suggested.
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Affiliation(s)
- W Deng
- School of Nursing, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - S T Cheung
- School of Nursing, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - S W Tsao
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - X M Wang
- School of Nursing, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - A F Y Tiwari
- School of Nursing, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
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47
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Interactions of fluorescent dye SYBR Green I with natural and 7-deazaguanine-modified DNA studied by fluorescence and electrochemical methods. MONATSHEFTE FUR CHEMIE 2015. [DOI: 10.1007/s00706-015-1578-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Fernández Larrosa PN, Ruíz Grecco M, Mengual Gómez D, Alvarado CV, Panelo LC, Rubio MF, Alonso DF, Gómez DE, Costas MA. RAC3 more than a nuclear receptor coactivator: a key inhibitor of senescence that is downregulated in aging. Cell Death Dis 2015; 6:e1902. [PMID: 26469953 PMCID: PMC4632280 DOI: 10.1038/cddis.2015.218] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 06/24/2015] [Accepted: 07/01/2015] [Indexed: 11/10/2022]
Abstract
Receptor-associated coactivator 3 (RAC3) is a nuclear receptor coactivator usually overexpressed in tumors that exerts oncogenic functions in the cytoplasm and the nucleus. Although as part of its oncogenic actions it was previously identified as an inhibitor of apoptosis and autophagy, its expression is required in order to preserve the pluripotency and embryonic stem cell self-renewal. In this work we investigated its role in cellular senescence. We found that RAC3 overexpression in the nontumoral HEK293 cells inhibits the premature senescence induced by hydrogen peroxide or rapamycin. The mechanism involves not only the inhibition of autophagy early induced by these stimuli in the pathway to senescence, but also the increase in levels and nuclear localization of both the cell cycle suppressors p53/p21 and the longevity promoters FOXO1A, FOXO3A and SIRT1. Furthermore, we found that RAC3 overexpression is required in order to maintain the telomerase activity. In tumoral HeLa cells its activity was inhibited by depletion of RAC3 inducing replicative senescence. Moreover, we demonstrated that in vivo, levels of RAC3 are downregulated in the liver from aged as compared with young rats, whereas the levels of p21 are increased, correlating with the expected senescent cell contents in aged tissues. A similar downregulation of RAC3 was observed in the premature and replicative senescence of human fetal WI-38 cells and premature senescence of hepatocyte HepG2 cell line. Taken together, all these results demonstrate that RAC3 is an inhibitor of senescence whose downregulation in aged individuals could be probably a tumor suppressor mechanism, avoiding the clonal expansion of risky old cells having damaged DNA.
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Affiliation(s)
- P N Fernández Larrosa
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
| | - M Ruíz Grecco
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
| | - D Mengual Gómez
- Laboratorio de Oncología Molecular, Universidad Nacional de Quilmes, R. Sáenz Peña 352, Bernal, Buenos Aires B1876BXD Argentina
| | - C V Alvarado
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
| | - L C Panelo
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
| | - M F Rubio
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
| | - D F Alonso
- Laboratorio de Oncología Molecular, Universidad Nacional de Quilmes, R. Sáenz Peña 352, Bernal, Buenos Aires B1876BXD Argentina
| | - D E Gómez
- Laboratorio de Oncología Molecular, Universidad Nacional de Quilmes, R. Sáenz Peña 352, Bernal, Buenos Aires B1876BXD Argentina
| | - M A Costas
- Laboratorio de Biología Molecular y Apoptosis, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Combatientes de Malvinas 3150, Buenos Aires C1427ARO, Argentina
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49
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Castillo-González D, Mergny JL, De Rache A, Pérez-Machado G, Cabrera-Pérez MA, Nicolotti O, Introcaso A, Mangiatordi GF, Guédin A, Bourdoncle A, Garrigues T, Pallardó F, Cordeiro MNDS, Paz-y-Miño C, Tejera E, Borges F, Cruz-Monteagudo M. Harmonization of QSAR Best Practices and Molecular Docking Provides an Efficient Virtual Screening Tool for Discovering New G-Quadruplex Ligands. J Chem Inf Model 2015; 55:2094-110. [DOI: 10.1021/acs.jcim.5b00415] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daimel Castillo-González
- ARNA Laboratory, IECB, University of Bordeaux, F-33600 Pessac, France
- ARNA Laboratory,
INSERM, U869, F-33000 Bordeaux, France
| | - Jean-Louis Mergny
- ARNA Laboratory, IECB, University of Bordeaux, F-33600 Pessac, France
- ARNA Laboratory,
INSERM, U869, F-33000 Bordeaux, France
| | - Aurore De Rache
- ARNA Laboratory, IECB, University of Bordeaux, F-33600 Pessac, France
- ARNA Laboratory,
INSERM, U869, F-33000 Bordeaux, France
| | - Gisselle Pérez-Machado
- Molecular Simulation and
Drug Design Group, Centro de Bioactivos Químicos (CBQ), Central University of Las Villas, Santa Clara, Villa Clara 54830, Cuba
- Department of Physiology,
Faculty of Medicine, University of Valencia, Valencia 46010, Valencia, Spain
- Department
of Pharmacy and Pharmaceutical Technology, University of Valencia, Burjassot 46100, Valencia, Spain
| | - Miguel Angel Cabrera-Pérez
- Molecular Simulation and
Drug Design Group, Centro de Bioactivos Químicos (CBQ), Central University of Las Villas, Santa Clara, Villa Clara 54830, Cuba
- Department
of Pharmacy and Pharmaceutical Technology, University of Valencia, Burjassot 46100, Valencia, Spain
- Department of Engineering, Area of Pharmacy and Pharmaceutical
Technology, Miguel Hernández University, 03550 Sant Joan d’Alacant, Alicante, Alicante, Spain
| | - Orazio Nicolotti
- Dipartimento
di Farmacia-Scienze, Università degli Studi di Bari “Aldo Moro″, Via Orabona 4, 70125 Bari, Bari, Italy
| | - Antonellina Introcaso
- Dipartimento
di Farmacia-Scienze, Università degli Studi di Bari “Aldo Moro″, Via Orabona 4, 70125 Bari, Bari, Italy
| | - Giuseppe Felice Mangiatordi
- Dipartimento
di Farmacia-Scienze, Università degli Studi di Bari “Aldo Moro″, Via Orabona 4, 70125 Bari, Bari, Italy
| | - Aurore Guédin
- ARNA Laboratory, IECB, University of Bordeaux, F-33600 Pessac, France
- ARNA Laboratory,
INSERM, U869, F-33000 Bordeaux, France
| | - Anne Bourdoncle
- ARNA Laboratory, IECB, University of Bordeaux, F-33600 Pessac, France
- ARNA Laboratory,
INSERM, U869, F-33000 Bordeaux, France
| | - Teresa Garrigues
- Department
of Pharmacy and Pharmaceutical Technology, University of Valencia, Burjassot 46100, Valencia, Spain
| | - Federico Pallardó
- Department of Physiology,
Faculty of Medicine, University of Valencia, Valencia 46010, Valencia, Spain
| | | | - Cesar Paz-y-Miño
- Instituto de Investigaciones
Biomédicas (IIB), Universidad de Las Américas, 170513 Quito, Pichincha, Ecuador
| | - Eduardo Tejera
- Instituto de Investigaciones
Biomédicas (IIB), Universidad de Las Américas, 170513 Quito, Pichincha, Ecuador
| | | | - Maykel Cruz-Monteagudo
- Instituto de Investigaciones
Biomédicas (IIB), Universidad de Las Américas, 170513 Quito, Pichincha, Ecuador
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50
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Chiba K, Johnson JZ, Vogan JM, Wagner T, Boyle JM, Hockemeyer D. Cancer-associated TERT promoter mutations abrogate telomerase silencing. eLife 2015. [PMID: 26194807 PMCID: PMC4507476 DOI: 10.7554/elife.07918] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Mutations in the human telomerase reverse transcriptase (TERT) promoter are the most frequent non-coding mutations in cancer, but their molecular mechanism in tumorigenesis has not been established. We used genome editing of human pluripotent stem cells with physiological telomerase expression to elucidate the mechanism by which these mutations contribute to human disease. Surprisingly, telomerase-expressing embryonic stem cells engineered to carry any of the three most frequent TERT promoter mutations showed only a modest increase in TERT transcription with no impact on telomerase activity. However, upon differentiation into somatic cells, which normally silence telomerase, cells with TERT promoter mutations failed to silence TERT expression, resulting in increased telomerase activity and aberrantly long telomeres. Thus, TERT promoter mutations are sufficient to overcome the proliferative barrier imposed by telomere shortening without additional tumor-selected mutations. These data establish that TERT promoter mutations can promote immortalization and tumorigenesis of incipient cancer cells. DOI:http://dx.doi.org/10.7554/eLife.07918.001 The bulk of the DNA in the human genome is divided between 23 pairs of chromosomes. The ends of these chromosomes contain a repetitive stretch of DNA known as a telomere. Every time a cell divides, a portion of the telomere is lost and can be restored by an enzyme called telomerase. If the telomeres shorten below a critical length, the cell can no longer divide and eventually dies. Thus, long telomeres increase the number of times a cell can divide. In the majority of human cells—with the exception of stem cells—telomerase activity is absent due to the down regulation of the active protein component (called TERT) after birth. Therefore, the telomeres in these cells shorten after each cell division. However, 90% of human cancers have very high TERT activity, which enables them to divide continuously to drive tumor growth. Genes are sections of DNA that code for proteins and other molecules. The start of a gene contains a region known as the promoter, which controls when and where in the body the gene is active. Cancer cells often contain mutations in the promoter of the gene that encodes TERT. However, it remains poorly understood how these mutations lead to the formation of tumors. Chiba et al. have now used a technique called genome editing to introduce mutations that are commonly found in cancer cells into the promoter of the gene for TERT in human embryonic stem cells. Unexpectedly, these changes did not increase the activity of the telomerase enzyme in these cells, nor did they increase the length of the telomeres. Chiba et al. next caused these genetically engineered stem cells to develop into more specialized cell types—such as nerve cells. These ‘differentiated’ cells normally silence the gene that encodes TERT, but the mutations prevented the gene from being silenced. This led to abnormally high levels of telomerase activity and long telomeres. The experiments also showed that TERT activity in these cells was similar to that found in cancer cells that can divide indefinitely. Cells containing the promoter mutations were then injected into mice. The cells formed a mass of tumors that contained very long telomeres. These results together suggest that cancer-causing mutations in the gene for TERT stop this gene from being properly silenced in more specialized cells, and that this, on its own, can promote the formation of tumors. These findings are likely to underpin future efforts to treat cancers by targeting the expression and activity of the telomerase enzyme. DOI:http://dx.doi.org/10.7554/eLife.07918.002
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Affiliation(s)
- Kunitoshi Chiba
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Joshua Z Johnson
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Jacob M Vogan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Tina Wagner
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - John M Boyle
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Dirk Hockemeyer
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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