1
|
Bartle L, Wellinger RJ. Methods that shaped telomerase research. Biogerontology 2024; 25:249-263. [PMID: 37903970 PMCID: PMC10998806 DOI: 10.1007/s10522-023-10073-8] [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: 08/08/2023] [Accepted: 09/30/2023] [Indexed: 11/01/2023]
Abstract
Telomerase, the ribonucleoprotein (RNP) responsible for telomere maintenance, has a complex life. Complex in that it is made of multiple proteins and an RNA, and complex because it undergoes many changes, and passes through different cell compartments. As such, many methods have been developed to discover telomerase components, delve deep into understanding its structure and function and to figure out how telomerase biology ultimately relates to human health and disease. While some old gold-standard methods are still key for determining telomere length and measuring telomerase activity, new technologies are providing promising new ways to gain detailed information that we have never had access to before. Therefore, we thought it timely to briefly review the methods that have revealed information about the telomerase RNP and outline some of the remaining questions that could be answered using new methodology.
Collapse
Affiliation(s)
- Louise Bartle
- Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Applied Cancer Research Pavilion, 3201 rue Jean-Mignault, Sherbrooke, QC, J1E 4K8, Canada
| | - Raymund J Wellinger
- Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Applied Cancer Research Pavilion, 3201 rue Jean-Mignault, Sherbrooke, QC, J1E 4K8, Canada.
| |
Collapse
|
2
|
Borges G, Benslimane Y, Harrington L. A CRISPR base editing approach for the functional assessment of telomere biology disorder-related genes in human health and aging. Biogerontology 2024; 25:361-378. [PMID: 38310618 PMCID: PMC10998809 DOI: 10.1007/s10522-024-10094-x] [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: 11/28/2023] [Accepted: 01/06/2024] [Indexed: 02/06/2024]
Abstract
Telomere Biology Disorders (TBDs) are a group of rare diseases characterized by the presence of short and/or dysfunctional telomeres. They comprise a group of bone marrow failure syndromes, idiopathic pulmonary fibrosis, and liver disease, among other diseases. Genetic alterations (variants) in the genes responsible for telomere homeostasis have been linked to TBDs. Despite the number of variants already identified as pathogenic, an even more significant number must be better understood. The study of TBDs is challenging since identifying these variants is difficult due to their rareness, it is hard to predict their impact on the disease onset, and there are not enough samples to study. Most of our knowledge about pathogenic variants comes from assessing telomerase activity from patients and their relatives affected by a TBD. However, we still lack a cell-based model to identify new variants and to study the long-term impact of such variants on the genes involved in TBDs. Herein, we present a cell-based model using CRISPR base editing to mutagenize the endogenous alleles of 21 genes involved in telomere biology. We identified key residues in the genes encoding 17 different proteins impacting cell growth. We provide functional evidence for variants of uncertain significance in patients with TBDs. We also identified variants resistant to telomerase inhibition that, similar to cells expressing wild-type telomerase, exhibited increased tumorigenic potential using an in vitro tumour growth assay. We believe that such cell-based approaches will significantly advance our understanding of the biology of TBDs and may contribute to the development of new therapies for this group of diseases.
Collapse
Affiliation(s)
- Gustavo Borges
- Departments of Medicine and Biochemistry and Molecular Medicine, Molecular Biology Programme, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, H3T 1J4, Canada
| | - Yahya Benslimane
- Departments of Medicine and Biochemistry and Molecular Medicine, Molecular Biology Programme, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, H3T 1J4, Canada
| | - Lea Harrington
- Departments of Medicine and Biochemistry and Molecular Medicine, Molecular Biology Programme, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, H3T 1J4, Canada.
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5G 1L7, Canada.
| |
Collapse
|
3
|
Liu M, Zhang Y, Jian Y, Gu L, Zhang D, Zhou H, Wang Y, Xu ZX. The regulations of telomerase reverse transcriptase (TERT) in cancer. Cell Death Dis 2024; 15:90. [PMID: 38278800 PMCID: PMC10817947 DOI: 10.1038/s41419-024-06454-7] [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: 09/22/2023] [Revised: 01/04/2024] [Accepted: 01/08/2024] [Indexed: 01/28/2024]
Abstract
Abnormal activation of telomerase occurs in most cancer types, which facilitates escaping from cell senescence. As the key component of telomerase, telomerase reverse transcriptase (TERT) is regulated by various regulation pathways. TERT gene changing in its promoter and phosphorylation respectively leads to TERT ectopic expression at the transcription and protein levels. The co-interacting factors play an important role in the regulation of TERT in different cancer types. In this review, we focus on the regulators of TERT and these downstream functions in cancer regulation. Determining the specific regulatory mechanism will help to facilitate the development of a cancer treatment strategy that targets telomerase and cancer cell senescence. As the most important catalytic subunit component of telomerase, TERT is rapidly regulated by transcriptional factors and PTM-related activation. These changes directly influence TERT-related telomere maintenance by regulating telomerase activity in telomerase-positive cancer cells, telomerase assembly with telomere-binding proteins, and recruiting telomerase to the telomere. Besides, there are also non-canonical functions that are influenced by TERT, including the basic biological functions of cancer cells, such as proliferation, apoptosis, cell cycle regulation, initiating cell formation, EMT, and cell invasion. Other downstream effects are the results of the influence of transcriptional factors by TERT. Currently, some small molecular inhibitors of TERT and TERT vaccine are under research as a clinical therapeutic target. Purposeful work is in progress.
Collapse
Affiliation(s)
- Mingdi Liu
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China
| | - Yuning Zhang
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China
| | - Yongping Jian
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China
| | - Liting Gu
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China
| | - Dan Zhang
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China
| | - Honglan Zhou
- Department of Urology, The First Hospital of Jilin University, Changchun, 130021, Jilin, China.
| | - Yishu Wang
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China.
| | - Zhi-Xiang Xu
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun, 130021, Jilin, China.
- Department of Urology, The First Hospital of Jilin University, Changchun, 130021, Jilin, China.
| |
Collapse
|
4
|
Vellingiri B, Balasubramani K, Iyer M, Raj N, Elangovan A, Song K, Yeo HC, Jayakumar N, Kinoshita M, Thangarasu R, Narayanasamy A, Dayem AA, Prajapati VK, Gopalakrishnan AV, Cho SG. Role of Telomeres and Telomerase in Parkinson's Disease-A New Theranostics? Adv Biol (Weinh) 2023; 7:e2300097. [PMID: 37590305 DOI: 10.1002/adbi.202300097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/19/2023] [Indexed: 08/19/2023]
Abstract
Parkinson's disease (PD) is a complex condition that is significantly influenced by oxidative stress and inflammation. It is also suggested that telomere shortening (TS) is regulated by oxidative stress which leads to various diseases including age-related neurodegenerative diseases like PD. Thus, it is anticipated that PD would result in TS of peripheral blood mononuclear cells (PBMCs). Telomeres protect the ends of eukaryotic chromosomes preserving them against fusion and destruction. The TS is a normal process because DNA polymerase is unable to replicate the linear ends of the DNA due to end replication complications and telomerase activity in various cell types counteracts this process. PD is usually observed in the aged population and progresses over time therefore, disparities among telomere length in PBMCs of PD patients are recorded and it is still a question whether it has any useful role. Here, the likelihood of telomere attrition in PD and its implications concerning microglia activation, ageing, oxidative stress, and the significance of telomerase activators are addressed. Also, the possibility of telomeres and telomerase as a diagnostic and therapeutic biomarker in PD is discussed.
Collapse
Affiliation(s)
- Balachandar Vellingiri
- Stem Cell and Regenerative Medicine/Translational Research, Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda, Punjab, 151401, India
| | - Kiruthika Balasubramani
- Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India
| | - Mahalaxmi Iyer
- Department of Biotechnology, Karpagam Academy of Higher Education (Deemed to be University), Coimbatore, Tamil Nadu, 641021, India
| | - Neethu Raj
- Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India
| | - Ajay Elangovan
- Stem Cell and Regenerative Medicine/Translational Research, Department of Zoology, School of Basic Sciences, Central University of Punjab, Bathinda, Punjab, 151401, India
| | - Kwonwoo Song
- Department of Stem Cell and Regenerative Biotechnology, Molecular and Cellular Reprogramming Center and Institute of Advanced Regenerative Science, Konkuk University, Seoul, 05029, Republic of Korea
| | - Han-Cheol Yeo
- Department of Stem Cell and Regenerative Biotechnology, Molecular and Cellular Reprogramming Center and Institute of Advanced Regenerative Science, Konkuk University, Seoul, 05029, Republic of Korea
| | - Namitha Jayakumar
- Department of Biotechnology, Sri Ramakrishna College of Arts and Science, Coimbatore, Tamil Nadu, 641006, India
| | - Masako Kinoshita
- Department of Neurology, National Hospital Organization Utano National Hospital, Ondoyama-Cho, Narutaki, Ukyo-Ku, Kyoto, 616-8255, Japan
| | - Ravimanickam Thangarasu
- Department of Zoology, School of Science, Tamil Nadu Open University, Saidapet, Chennai, 600015, India
| | - Arul Narayanasamy
- Disease Proteomics Laboratory, Department of Zoology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India
| | - Ahmed Abdal Dayem
- Department of Stem Cell and Regenerative Biotechnology, Molecular and Cellular Reprogramming Center and Institute of Advanced Regenerative Science, Konkuk University, Seoul, 05029, Republic of Korea
| | - Vijay Kumar Prajapati
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, Dhaula Kuan, New Delhi, 110021, India
| | - Abilash Valsala Gopalakrishnan
- Department of Biomedical Sciences, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India
| | - Ssang-Goo Cho
- Department of Stem Cell and Regenerative Biotechnology, Molecular and Cellular Reprogramming Center and Institute of Advanced Regenerative Science, Konkuk University, Seoul, 05029, Republic of Korea
| |
Collapse
|
5
|
Cheng Q, Liu C, Chen Q, Luo W, He TC, Yang D. Establishing and characterizing human stem cells from the apical papilla immortalized by hTERT gene transfer. Front Cell Dev Biol 2023; 11:1158936. [PMID: 37283947 PMCID: PMC10239932 DOI: 10.3389/fcell.2023.1158936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 05/09/2023] [Indexed: 06/08/2023] Open
Abstract
Stem cells from the apical papilla (SCAPs) are promising candidates for regenerative endodontic treatment and tissue regeneration in general. However, harvesting enough cells from the limited apical papilla tissue is difficult, and the cells lose their primary phenotype over many passages. To get over these challenges, we immortalized human SCAPs with lentiviruses overexpressing human telomerase reverse transcriptase (hTERT). Human immortalized SCAPs (hiSCAPs) exhibited long-term proliferative activity without tumorigenic potential. Cells also expressed mesenchymal and progenitor biomarkers and exhibited multiple differentiation potentials. Interestingly, hiSCAPs gained a stronger potential for osteogenic differentiation than the primary cells. To further investigate whether hiSCAPs could become prospective seed cells in bone tissue engineering, in vitro and in vivo studies were performed, and the results indicated that hiSCAPs exhibited strong osteogenic differentiation ability after infection with recombinant adenoviruses expressing BMP9 (AdBMP9). In addition, we revealed that BMP9 could upregulate ALK1 and BMPRII, leading to an increase in phosphorylated Smad1 to induce the osteogenic differentiation of hiSCAPs. These results support the application of hiSCAPs in tissue engineering/regeneration schemes as a stable stem cell source for osteogenic differentiation and biomineralization, which could be further used in stem cell-based clinical therapies.
Collapse
Affiliation(s)
- Qianyu Cheng
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
- College of Stomatology, Chongqing Medical University, Chongqing, China
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
| | - Chang Liu
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
- College of Stomatology, Chongqing Medical University, Chongqing, China
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
| | - Qiuman Chen
- Department of Stomatology, Hainan Women and Children’s Medical Center, Haikou, China
| | - Wenping Luo
- Laboratory Animal Center, Southwest University, Chongqing, China
| | - Tong-Chuan He
- Department of Orthopaedic Surgery and Rehabilitation Medicine, Molecular Oncology Laboratory, The University of Chicago Medical Center, Chicago, IL, United States
| | - Deqin Yang
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
- College of Stomatology, Chongqing Medical University, Chongqing, China
- Department of Endodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
6
|
Defining the Emergence of New Immunotherapy Approaches in Breast Cancer: Role of Myeloid-Derived Suppressor Cells. Int J Mol Sci 2023; 24:ijms24065208. [PMID: 36982282 PMCID: PMC10048951 DOI: 10.3390/ijms24065208] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/24/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Breast cancer (BC) continues to be the most diagnosed tumor in women and a very heterogeneous disease both inter- and intratumoral, mainly given by the variety of molecular profiles with different biological and clinical characteristics. Despite the advancements in early detection and therapeutic strategies, the survival rate is low in patients who develop metastatic disease. Therefore, it is mandatory to explore new approaches to achieve better responses. In this regard, immunotherapy arose as a promising alternative to conventional treatments due to its ability to modulate the immune system, which may play a dual role in this disease since the relationship between the immune system and BC cells depends on several factors: the tumor histology and size, as well as the involvement of lymph nodes, immune cells, and molecules that are part of the tumor microenvironment. Particularly, myeloid-derived suppressor cell (MDSC) expansion is one of the major immunosuppressive mechanisms used by breast tumors since it has been associated with worse clinical stage, metastatic burden, and poor efficacy of immunotherapies. This review focuses on the new immunotherapies in BC in the last five years. Additionally, the role of MDSC as a therapeutic target in breast cancer will be described.
Collapse
|
7
|
Derivation of the Immortalized Cell Line UM51-PrePodo-hTERT and Its Responsiveness to Angiotensin II and Activation of the RAAS Pathway. Cells 2023; 12:cells12030342. [PMID: 36766685 PMCID: PMC9913089 DOI: 10.3390/cells12030342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/12/2023] [Accepted: 01/14/2023] [Indexed: 01/18/2023] Open
Abstract
Recent demographic studies predict there will be a considerable increase in the number of elderly people within the next few decades. Aging has been recognized as one of the main risk factors for the world's most prevalent diseases such as neurodegenerative disorders, cancer, cardiovascular disease, and metabolic diseases. During the process of aging, a gradual loss of tissue volume and organ function is observed, which is partially caused by replicative senescence. The capacity of cellular proliferation and replicative senescence is tightly regulated by their telomere length. When telomere length is critically shortened with progressive cell division, cells become proliferatively arrested, and DNA damage response and cellular senescence are triggered, whereupon the "Hayflick limit" is attained at this stage. Podocytes are a cell type found in the kidney glomerulus where they have major roles in blood filtration. Mature podocytes are terminal differentiated cells that are unable to undergo cell division in vivo. For this reason, the establishment of primary podocyte cell cultures has been very challenging. In our present study, we present the successful immortalization of a human podocyte progenitor cell line, of which the primary cells were isolated directly from the urine of a 51-year-old male. The immortalized cell line was cultured over the course of one year (~100 passages) with high proliferation capacity, endowed with contact inhibition and P53 expression. Furthermore, by immunofluorescence-based expression and quantitative real-time PCR for the podocyte markers CD2AP, LMX1B, NPHS1, SYNPO and WT1, we confirmed the differentiation capacity of the immortalized cells. Finally, we evaluated and confirmed the responsiveness of the immortalized cells on the main mediator angiotensin II (ANGII) of the renin-angiotensin system (RAAS). In conclusion, we have shown that it is possible to bypass cellular replicative senescence (Hayflick limit) by TERT-driven immortalization of human urine-derived pre-podocyte cells from a 51-year-old African male.
Collapse
|
8
|
Ott P, Araúzo-Bravo MJ, Hoffmann MJ, Poyet C, Bendhack ML, Santourlidis S, Erichsen L. Differential DNA Methylation of THOR and hTAPAS in the Regulation of hTERT and the Diagnosis of Cancer. Cancers (Basel) 2022; 14:cancers14184384. [PMID: 36139544 PMCID: PMC9497117 DOI: 10.3390/cancers14184384] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Because of its high prevalence of >45% in 9 out of 11 (82%) cancer types screened, THOR hypermethylation has been suggested to be a frequent telomerase-activating mechanism in hTERT-expressing tumor types, e.g., in cancers of the prostate, breast, blood, colon, lung, bladder, and brain. In this prime example, we present detailed DNA methylation profiles in urothelial cancer that reveal the exact positions of the most differentially methylated CpG dinucleotides within the THOR region in order to design an efficient Methylation-Specific PCR (MSPCR) approach for diagnostic and prognostic purposes. Furthermore, our data suggest an epigenetic mechanism regulating hTERT expression through the methylation status of THOR and lncRNA hTAPAS. Abstract Background: Although DNA methylation in the gene promoters usually represses gene expression, the TERT hypermethylated oncological region (THOR) located 5′ of the hTERT gene is hypermethylated when hTERT is expressed in diverse cancer types, including urothelial cancer (UC). Methods: Comprehensive MeDIP and DNA methylation array analyses complemented by the technically independent method of bisulfite genomic sequencing were applied on pathologically reviewed and classified urothelial carcinoma specimens and healthy urothelial tissue samples to reveal the methylation status of THOR in detail. Results: The detailed DNA methylation profiles reveal the exact positions of differentially methylated CpG dinucleotides within THOR in urothelial cancer and provide evidence ofa diverging role of methylation of these CpGs in the regulation of hTERT. In particular, our data suggest a regulating mechanism in which THOR methylation acts on hTERT expression through epigenetic silencing of the lncRNA hTERT antisense promoter-associated (hTAPAS), which represses hTERT. Conclusions: These findings precisely define the most differentially methylated CpGs of THOR in early urothelial cancer, enabling optimal design of Methylation-Specific PCR (MSPCR) primers to reliably probe these methylation differences for diagnostic and prognostic purposes. In addition, this strategy presents a prime example that is also applicable to many other malignancies. Finally, the first evidence for the underlying epigenetic mechanism regulating hTERT expression through the methylation status of THOR is provided.
Collapse
Affiliation(s)
- Pauline Ott
- Epigenetics Core Laboratory, Institute of Transplantation Diagnostics and Cell Therapeutics, Medical Faculty, Heinrich-Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Marcos J. Araúzo-Bravo
- Group of Computational Biology and Systems Biomedicine, Biodonostia Health Research Institute, 20014 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Michèle J. Hoffmann
- Department of Urology, Medical Faculty, Heinrich-Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Cedric Poyet
- Department of Urology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Marcelo L. Bendhack
- Department of Urology, University Hospital, Positivo University, Curitiba 80420-011, Brazil
| | - Simeon Santourlidis
- Epigenetics Core Laboratory, Institute of Transplantation Diagnostics and Cell Therapeutics, Medical Faculty, Heinrich-Heine University Duesseldorf, 40225 Duesseldorf, Germany
- Correspondence: (S.S.); (L.E.)
| | - Lars Erichsen
- Epigenetics Core Laboratory, Institute of Transplantation Diagnostics and Cell Therapeutics, Medical Faculty, Heinrich-Heine University Duesseldorf, 40225 Duesseldorf, Germany
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine University Duesseldorf, 40225 Duesseldorf, Germany
- Correspondence: (S.S.); (L.E.)
| |
Collapse
|
9
|
Giha HA, Joatar FE, AlDehaini DMB, Malalla ZHA, Ali ME, Al Qarni AA. Association of obesity in T2DM with differential polymorphism of ghrelin, growth hormone secretagogue receptor-1 and telomeres maintenance genes. Horm Mol Biol Clin Investig 2022; 43:297-306. [PMID: 35446515 DOI: 10.1515/hmbci-2021-0063] [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: 07/23/2021] [Accepted: 03/12/2022] [Indexed: 11/15/2022]
Abstract
BACKGROUND Although obesity and T2DM comorbidity is too frequent, the molecular basis of diabetic obesity is largely unexplained and barely investigated. MATERIALS Cross-sectional studies were conducted in Kingdom of Saudi Arabia (KSA) in 2013 and Kuwait in 2019. Fasting blood samples were obtained from a total of 216 T2DM patients (104 from KSA) and 193 nondiabetic subjects (93 from KSA) after their consents. Eight SNPs in 5 genes known to be associated with both obesity and T2DM, ghrelin (GHRL) and growth hormone secretagogue receptor -GHSR (KSA) and telomeres maintenance genes (Kuwait) were genotyped by rtPCR. Both patients and controls were grouped into obese and non-obese and sub-grouped into 4-BMI- grades: normal, overweight (OW), obese (OBS) and severely obese (SOBS). RESULTS Showed that the only SNP which was distinguished between all groups/subgroups in all study subjects was the ACYP2 rs6713088G/C, where the common CC genotype was under-expressed in the obese compared to non-obese diabetics (17.8% vs. 40.4%, p 0.01) and between the 4-BMI-grade (p 0.025). Interestingly the same genotype was over-expressed in obese compared to non-obese non-diabetics (50% vs. 27.6%, p 0.04). Furthermore, the GHRL (rs27647C/T), GHSR (rs509030G/C) and TERC (rs12696304G/C) MAFs were significantly low in normal BMI patients; p= 0.034, 0.008 and 0.011, respectively. CONCLUSIONS This is the first report about the molecular distinction between the obese and non-obese diabetics, it showed the association of rs6713088G/C mutant allele with diabetic obesity, while the GHRL, GHSR and TERC SNPs were differentially expressed based on the BMI-grades.
Collapse
Affiliation(s)
- Hayder A Giha
- Medical Biochemistry and Molecular Biology, Khartoum, Sudan
| | - Faris E Joatar
- Clinical Biochemistry Laboratory, King Abdulaziz Hospital, Ministry of National Guard Health affairs, Al Ahsa, Saudi Arabia
| | | | - Zainab H A Malalla
- Medical Department of Biochemistry, College of Medicine and Medical Sciences (CMMS), Arabian Gulf University (AGU), Manama, Kingdom of Bahrain
| | - Muhalab E Ali
- Medical Department of Biochemistry, College of Medicine and Medical Sciences (CMMS), Arabian Gulf University (AGU), Manama, Kingdom of Bahrain
| | - Ali A Al Qarni
- Endocrinology and Metabolism Section, King Abdulaziz Hospital, Ministry of National Guard Health Affairs, King Abdullah Medical Research Center-Estern Region, Al Ahsa, Saudi Arabia
| |
Collapse
|
10
|
Dey A, Monroy-Eklund A, Klotz K, Saha A, Davis J, Li B, Laederach A, Chakrabarti K. In vivo architecture of the telomerase RNA catalytic core in Trypanosoma brucei. Nucleic Acids Res 2021; 49:12445-12466. [PMID: 34850114 PMCID: PMC8643685 DOI: 10.1093/nar/gkab1042] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/11/2021] [Accepted: 10/15/2021] [Indexed: 01/07/2023] Open
Abstract
Telomerase is a unique ribonucleoprotein (RNP) reverse transcriptase that utilizes its cognate RNA molecule as a template for telomere DNA repeat synthesis. Telomerase contains the reverse transcriptase protein, TERT and the template RNA, TR, as its core components. The 5'-half of TR forms a highly conserved catalytic core comprising of the template region and adjacent domains necessary for telomere synthesis. However, how telomerase RNA folding takes place in vivo has not been fully understood due to low abundance of the native RNP. Here, using unicellular pathogen Trypanosoma brucei as a model, we reveal important regional folding information of the native telomerase RNA core domains, i.e. TR template, template boundary element, template proximal helix and Helix IV (eCR4-CR5) domain. For this purpose, we uniquely combined in-cell probing with targeted high-throughput RNA sequencing and mutational mapping under three conditions: in vivo (in WT and TERT-/- cells), in an immunopurified catalytically active telomerase RNP complex and ex vivo (deproteinized). We discover that TR forms at least two different conformers with distinct folding topologies in the insect and mammalian developmental stages of T. brucei. Also, TERT does not significantly affect the RNA folding in vivo, suggesting that the telomerase RNA in T. brucei exists in a conformationally preorganized stable structure. Our observed differences in RNA (TR) folding at two distinct developmental stages of T. brucei suggest that important conformational changes are a key component of T. brucei development.
Collapse
Affiliation(s)
- Abhishek Dey
- Department of Biological Sciences, University of North Carolina, Charlotte, NC 28223, USA
| | - Anais Monroy-Eklund
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Kaitlin Klotz
- Department of Biological Sciences, University of North Carolina, Charlotte, NC 28223, USA
| | - Arpita Saha
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, Cleveland, OH 44115, USA
| | - Justin Davis
- Department of Biological Sciences, University of North Carolina, Charlotte, NC 28223, USA
| | - Bibo Li
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, Cleveland, OH 44115, USA
| | - Alain Laederach
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Kausik Chakrabarti
- To whom correspondence should be addressed. Tel: +1 704 687 1882; Fax: +1 704 687 1488;
| |
Collapse
|
11
|
Lawing AM, McCoy M, Reinke BA, Sarkar SK, Smith FA, Wright D. A Framework for Investigating Rules of Life by Establishing Zones of Influence. Integr Comp Biol 2021; 61:2095-2108. [PMID: 34297089 DOI: 10.1093/icb/icab169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 06/26/2021] [Accepted: 07/20/2021] [Indexed: 12/18/2022] Open
Abstract
The incredible complexity of biological processes across temporal and spatial scales hampers defining common underlying mechanisms driving the patterns of life. However, recent advances in sequencing, big data analysis, machine learning, and molecular dynamics simulation have renewed the hope and urgency of finding potential hidden rules of life. There currently exists no framework to develop such synoptic investigations. Some efforts aim to identify unifying rules of life across hierarchical levels of time, space, and biological organization, but not all phenomena occur across all the levels of these hierarchies. Instead of identifying the same parameters and rules across levels, we posit that each level of a temporal and spatial scale and each level of biological organization has unique parameters and rules that may or may not predict outcomes in neighboring levels. We define this neighborhood, or the set of levels, across which a rule functions as the zone of influence. Here, we introduce the zone of influence framework and explain using three examples: (Smocovitis, 1992) randomness in biology, where we use a Poisson process to describe processes from protein dynamics to DNA mutations to gene expressions, (Leroi, 2014) island biogeography, and (Gropp, 2016) animal coloration. The zone of influence framework may enable researchers to identify which levels are worth investigating for a particular phenomenon and reframe the narrative of searching for a unifying rule of life to the investigation of how, when, and where various rules of life operate.
Collapse
Affiliation(s)
| | - Michael McCoy
- Department of Biology, East Carolina University, NC, USA
| | - Beth A Reinke
- Department of Biology, Northeastern Illinois University, IL, USA
| | | | - Felisa A Smith
- Department of Biology, University of New Mexico, NM, USA
| | - Derek Wright
- Department of Physics, Colorado School of Mines, CO, USA
| |
Collapse
|
12
|
Fajkus P, Peška V, Fajkus J, Sýkorová E. Origin and Fates of TERT Gene Copies in Polyploid Plants. Int J Mol Sci 2021; 22:1783. [PMID: 33670111 PMCID: PMC7916837 DOI: 10.3390/ijms22041783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 12/14/2022] Open
Abstract
The gene coding for the telomerase reverse transcriptase (TERT) is essential for the maintenance of telomeres. Previously we described the presence of three TERT paralogs in the allotetraploid plant Nicotiana tabacum, while a single TERT copy was identified in the paleopolyploid model plant Arabidopsis thaliana. Here we examine the presence, origin and functional status of TERT variants in allotetraploid Nicotiana species of diverse evolutionary ages and their parental genome donors, as well as in other diploid and polyploid plant species. A combination of experimental and in silico bottom-up analyses of TERT gene copies in Nicotiana polyploids revealed various patterns of retention or loss of parental TERT variants and divergence in their functions. RT-qPCR results confirmed the expression of all the identified TERT variants. In representative plant and green algal genomes, our synteny analyses show that their TERT genes were located in a conserved locus that became advantageous after the divergence of eudicots, and the gene was later translocated in several plant groups. In various diploid and polyploid species, translocation of TERT became fixed in target loci that show ancient synapomorphy.
Collapse
Affiliation(s)
- Petr Fajkus
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, CZ-61265 Brno, Czech Republic; (P.F.); (V.P.)
| | - Vratislav Peška
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, CZ-61265 Brno, Czech Republic; (P.F.); (V.P.)
| | - Jiří Fajkus
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, CZ-61265 Brno, Czech Republic; (P.F.); (V.P.)
- Laboratory of Functional Genomics and Proteomics, NCBR, Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic
| | - Eva Sýkorová
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, CZ-61265 Brno, Czech Republic; (P.F.); (V.P.)
| |
Collapse
|
13
|
Frascotti G, Galbiati E, Mazzucchelli M, Pozzi M, Salvioni L, Vertemara J, Tortora P. The Vault Nanoparticle: A Gigantic Ribonucleoprotein Assembly Involved in Diverse Physiological and Pathological Phenomena and an Ideal Nanovector for Drug Delivery and Therapy. Cancers (Basel) 2021; 13:cancers13040707. [PMID: 33572350 PMCID: PMC7916137 DOI: 10.3390/cancers13040707] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/03/2021] [Accepted: 02/03/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary In recent decades, a molecular complex referred to as vault nanoparticle has attracted much attention by the scientific community, due to its unique properties. At the molecular scale, it is a huge assembly consisting of 78 97-kDa polypeptide chains enclosing an internal cavity, wherein enzymes involved in DNA integrity maintenance and some small noncoding RNAs are accommodated. Basically, two reasons justify this interest. On the one hand, this complex represents an ideal tool for the targeted delivery of drugs, provided it is suitably engineered, either chemically or genetically; on the other hand, it has been shown to be involved in several cellular pathways and mechanisms that most often result in multidrug resistance. It is therefore expected that a better understanding of the physiological roles of this ribonucleoproteic complex may help develop new therapeutic strategies capable of coping with cancer progression. Here, we provide a comprehensive review of the current knowledge. Abstract The vault nanoparticle is a eukaryotic ribonucleoprotein complex consisting of 78 individual 97 kDa-“major vault protein” (MVP) molecules that form two symmetrical, cup-shaped, hollow halves. It has a huge size (72.5 × 41 × 41 nm) and an internal cavity, wherein the vault poly(ADP-ribose) polymerase (vPARP), telomerase-associated protein-1 (TEP1), and some small untranslated RNAs are accommodated. Plenty of literature reports on the biological role(s) of this nanocomplex, as well as its involvement in diseases, mostly oncological ones. Nevertheless, much has still to be understood as to how vault participates in normal and pathological mechanisms. In this comprehensive review, current understanding of its biological roles is discussed. By different mechanisms, vault’s individual components are involved in major cellular phenomena, which result in protection against cellular stresses, such as DNA-damaging agents, irradiation, hypoxia, hyperosmotic, and oxidative conditions. These diverse cellular functions are accomplished by different mechanisms, mainly gene expression reprogramming, activation of proliferative/prosurvival signaling pathways, export from the nucleus of DNA-damaging drugs, and import of specific proteins. The cellular functions of this nanocomplex may also result in the onset of pathological conditions, mainly (but not exclusively) tumor proliferation and multidrug resistance. The current understanding of its biological roles in physiological and pathological processes should also provide new hints to extend the scope of its exploitation as a nanocarrier for drug delivery.
Collapse
|
14
|
Schrumpfová PP, Fajkus J. Composition and Function of Telomerase-A Polymerase Associated with the Origin of Eukaryotes. Biomolecules 2020; 10:biom10101425. [PMID: 33050064 PMCID: PMC7658794 DOI: 10.3390/biom10101425] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 12/19/2022] Open
Abstract
The canonical DNA polymerases involved in the replication of the genome are unable to fully replicate the physical ends of linear chromosomes, called telomeres. Chromosomal termini thus become shortened in each cell cycle. The maintenance of telomeres requires telomerase—a specific RNA-dependent DNA polymerase enzyme complex that carries its own RNA template and adds telomeric repeats to the ends of chromosomes using a reverse transcription mechanism. Both core subunits of telomerase—its catalytic telomerase reverse transcriptase (TERT) subunit and telomerase RNA (TR) component—were identified in quick succession in Tetrahymena more than 30 years ago. Since then, both telomerase subunits have been described in various organisms including yeasts, mammals, birds, reptiles and fish. Despite the fact that telomerase activity in plants was described 25 years ago and the TERT subunit four years later, a genuine plant TR has only recently been identified by our group. In this review, we focus on the structure, composition and function of telomerases. In addition, we discuss the origin and phylogenetic divergence of this unique RNA-dependent DNA polymerase as a witness of early eukaryotic evolution. Specifically, we discuss the latest information regarding the recently discovered TR component in plants, its conservation and its structural features.
Collapse
Affiliation(s)
- Petra Procházková Schrumpfová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic;
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic
- Correspondence:
| | - Jiří Fajkus
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic;
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, 612 65 Brno, Czech Republic
| |
Collapse
|
15
|
The influence of TERC, TERT and ACYP2 genes polymorphisms on plasma telomerase concentration, telomeres length and T2DM. Gene 2020; 766:145127. [PMID: 32937184 DOI: 10.1016/j.gene.2020.145127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 07/20/2020] [Accepted: 09/01/2020] [Indexed: 11/21/2022]
Abstract
Telomeres are duplex tandem repeats of DNA sequence 5'-TTAGGG-3' at chromosomal ends synthesized by telomerase enzyme (TE). Telomeres length (TL) shortening is associated with age and age-related disorders. Recently, we demonstrated marked leukocytes TL (LTL) shortening in T2DM. To set the relationship between the TE, LTL and T2DM, we analyzed samples from 212 Kuwaiti subjects, 112 patients withT2DM and 100 non-diabetic subjects. The plasma TE and fasting insulin were measured by ELISA, the LTL was estimated by qPCR and three SNPs of genes related to TL; TERC rs12696304 (C/G), TERT rs2736100 (C/A) and ACYP2 rs6713088 (C/G) were genotyped by rtPCR. Results revealed comparable TE levels and alleles/genotypes between the cases and controls with no influence of either on the LTL. Interestingly, although the plasma concentration of the TE was generally low, it was significantly influenced by the TERT and ACYP2 but not TERC polymorphisms. The CC genotype carriers of rs2736100 (C/A) had significantly higher plasma TE levels compared to CA and AA carriers, p 0.009 and p 0.047, respectively, and the A-allele was associated with low TE, p 0.018. Similarly, significantly higher TE levels were detected in CC carriers of ACYP2 rs6713088 (C/G) compared with GC carriers, p 0.002, and the G-allele was associated with low TE, p 0.009. Finally, the TERT and ACYP2 polymorphisms had an influence on blood glucose levels. In conclusion, the telomeres shortening in T2DM was not due to TE deficiency or gene polymorphisms, while the TE levels were significantly associated with the TERT and ACYP2 but not TERC polymorphisms.
Collapse
|
16
|
Paudel BP, Moye AL, Abou Assi H, El-Khoury R, Cohen SB, Holien JK, Birrento ML, Samosorn S, Intharapichai K, Tomlinson CG, Teulade-Fichou MP, González C, Beck JL, Damha MJ, van Oijen AM, Bryan TM. A mechanism for the extension and unfolding of parallel telomeric G-quadruplexes by human telomerase at single-molecule resolution. eLife 2020; 9:56428. [PMID: 32723475 PMCID: PMC7426096 DOI: 10.7554/elife.56428] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 07/28/2020] [Indexed: 02/07/2023] Open
Abstract
Telomeric G-quadruplexes (G4) were long believed to form a protective structure at telomeres, preventing their extension by the ribonucleoprotein telomerase. Contrary to this belief, we have previously demonstrated that parallel-stranded conformations of telomeric G4 can be extended by human and ciliate telomerase. However, a mechanistic understanding of the interaction of telomerase with structured DNA remained elusive. Here, we use single-molecule fluorescence resonance energy transfer (smFRET) microscopy and bulk-phase enzymology to propose a mechanism for the resolution and extension of parallel G4 by telomerase. Binding is initiated by the RNA template of telomerase interacting with the G-quadruplex; nucleotide addition then proceeds to the end of the RNA template. It is only through the large conformational change of translocation following synthesis that the G-quadruplex structure is completely unfolded to a linear product. Surprisingly, parallel G4 stabilization with either small molecule ligands or by chemical modification does not always inhibit G4 unfolding and extension by telomerase. These data reveal that telomerase is a parallel G-quadruplex resolvase.
Collapse
Affiliation(s)
- Bishnu P Paudel
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.,Illawara Health and Medical Research Institute, Wollongong, Australia
| | - Aaron Lavel Moye
- Children's Medical Research Institute, University of Sydney, Westmead, Australia
| | - Hala Abou Assi
- Department of Chemistry, McGill University, Montreal, Canada
| | | | - Scott B Cohen
- Children's Medical Research Institute, University of Sydney, Westmead, Australia
| | - Jessica K Holien
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Australia
| | - Monica L Birrento
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.,Illawara Health and Medical Research Institute, Wollongong, Australia
| | - Siritron Samosorn
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok, Thailand
| | - Kamthorn Intharapichai
- Department of Biobased Materials Science, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan
| | | | - Marie-Paule Teulade-Fichou
- Institut Curie, PSL Research University, Orsay, France.,Université Paris Sud, Université Paris-Saclay, Orsay, France
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, Madrid, Spain
| | - Jennifer L Beck
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.,Illawara Health and Medical Research Institute, Wollongong, Australia
| | - Masad J Damha
- Department of Chemistry, McGill University, Montreal, Canada
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia.,Illawara Health and Medical Research Institute, Wollongong, Australia
| | - Tracy M Bryan
- Children's Medical Research Institute, University of Sydney, Westmead, Australia
| |
Collapse
|
17
|
Levstek T, Kozjek E, Dolžan V, Trebušak Podkrajšek K. Telomere Attrition in Neurodegenerative Disorders. Front Cell Neurosci 2020; 14:219. [PMID: 32760251 PMCID: PMC7373805 DOI: 10.3389/fncel.2020.00219] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/19/2020] [Indexed: 12/13/2022] Open
Abstract
Telomere attrition is increased in various disorders and is therefore a potential biomarker for diagnosis and/or prognosis of these disorders. The contribution of telomere attrition in the pathogenesis of neurodegenerative disorders is yet to be fully elucidated. We are reviewing the current knowledge regarding the telomere biology in two common neurodegenerative disorders, Alzheimer's disease (AD), and Parkinson's disease (PD). Furthermore, we are discussing future prospective of telomere research in these disorders. The majority of studies reported consistent evidence of the accelerated telomere attrition in AD patients, possibly in association with elevated oxidative stress levels. On the other hand in PD, various studies reported contradictory evidence regarding telomere attrition. Consequently, due to the low specificity and sensitivity, the clinical benefit of telomere length as a biomarker of neurodegenerative disease development and progression is not yet recognized. Nevertheless, longitudinal studies in large carefully selected cohorts might provide further elucidation of the complex involvement of the telomeres in the pathogenesis of neurodegenerative diseases. Telomere length maintenance is a complex process characterized by environmental, genetic, and epigenetic determinants. Thus, in addition to the selection of the study cohort, also the selection of analytical methods and types of biological samples for evaluation of the telomere attrition is of utmost importance.
Collapse
Affiliation(s)
- Tina Levstek
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Eva Kozjek
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Vita Dolžan
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Katarina Trebušak Podkrajšek
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Clinical Institute for Special Laboratory Diagnostics, University Children’s Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
18
|
Whittemore K, Derevyanko A, Martinez P, Serrano R, Pumarola M, Bosch F, Blasco MA. Telomerase gene therapy ameliorates the effects of neurodegeneration associated to short telomeres in mice. Aging (Albany NY) 2020; 11:2916-2948. [PMID: 31140977 PMCID: PMC6555470 DOI: 10.18632/aging.101982] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 05/17/2019] [Indexed: 12/26/2022]
Abstract
Neurodegenerative diseases associated with old age such as Alzheimer’s disease present major problems for society, and they currently have no cure. The telomere protective caps at the ends of chromosomes shorten with age, and when they become critically short, they can induce a persistent DNA damage response at chromosome ends, triggering secondary cellular responses such as cell death and cellular senescence. Mice and humans with very short telomeres owing to telomerase deficiencies have an earlier onset of pathologies associated with loss of the regenerative capacity of tissues. However, the effects of short telomeres in very low proliferative tissues such as the brain have not been thoroughly investigated. Here, we describe a mouse model of neurodegeneration owing to presence of short telomeres in the brain as the consequence of telomerase deficiency. Interestingly, we find similar signs of neurodegeneration in very old mice as the consequence of physiological mouse aging. Next, we demonstrate that delivery of telomerase gene therapy to the brain of these mice results in amelioration of some of these neurodegeneration phenotypes. These findings suggest that short telomeres contribute to neurodegeneration diseases with aging and that telomerase activation may have a therapeutic value in these diseases.
Collapse
Affiliation(s)
- Kurt Whittemore
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid 28029, Spain
| | - Aksinya Derevyanko
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid 28029, Spain
| | - Paula Martinez
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid 28029, Spain
| | - Rosa Serrano
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid 28029, Spain
| | - Martí Pumarola
- Unit of Murine and Comparative Pathology (UPMiC), Department of Animal Medicine and Surgery, Veterinary Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Barcelona, Spain.,Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Barcelona, Spain
| | - Fàtima Bosch
- Center of Animal Biotechnology and Gene Therapy, Department of Animal Medicine and Surgery, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain.,Center of Animal Biotechnology and Gene Therapy, Department of Biochemistry and Molecular Biology, School of Veterinary Medicine, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid 28029, Spain
| |
Collapse
|
19
|
Nozawa A, Ozeki M, Yasue S, Endo S, Kadowaki T, Ohnishi H, Muramatsu H, Hama A, Takahashi Y, Kojima S, Fukao T. Myelodysplastic syndromes in a pediatric patient with Cri du Chat syndrome with a ring chromosome 5. Int J Hematol 2020; 112:728-733. [PMID: 32519173 DOI: 10.1007/s12185-020-02909-7] [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] [Received: 11/29/2019] [Revised: 05/12/2020] [Accepted: 05/29/2020] [Indexed: 11/30/2022]
Abstract
Few hematological complications have previously been reported in association with Cri du Chat syndrome (CdCS). A case of myelodysplastic syndromes (MDS) in a pediatric patient with CdCS is herein presented. A 17-year-old female with CdCS caused by ring chromosome 5 was admitted to the hospital for investigation of a 1-month history of anemia. Based on the morphological findings of bone marrow, the patient was diagnosed with refractory cytopenia with multilineage dysplasia. The risk group was classified as intermediate-1 in the International Prognostic Scoring System (IPSS), and low in the revised IPSS. Assessment by microarray comparative genomic hybridization (CGH) identified the breakpoints of ring chromosome 5 as 46,XX,r(5)(p14.3q35.3). This revealed that the 5q terminal deletion did not include the common deleted region of MDS with del(5q). Treatment with azacitidine was initiated to control disease progression and improve quality of life. At baseline, the patient had a mean transfusion requirement of 3 units/month, which decreased to 2 units/month after six cycles of azacitidine and to 1 unit/month after 10 cycles of azacitidine. Cytopenia observed in the presented case seemed irrelevant to ring chromosome 5 which is the causative cytogenetic abnormality of CdCS, and further analyses may be needed to clarify the pathogenesis.
Collapse
Affiliation(s)
- Akifumi Nozawa
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Michio Ozeki
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan.
| | - Shiho Yasue
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Saori Endo
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Tomonori Kadowaki
- Department of Pediatrics, National Hospital Organization Nagara Medical Center, Gifu, 502-8558, Japan
| | - Hidenori Ohnishi
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Hideki Muramatsu
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, 466-8650, Japan
| | - Asahito Hama
- Department of Hematology and Oncology, Children's Medical Center, Japanese Red Cross Nagoya First Hospital, Nakamura-ku, Nagoya, 453-8511, Japan
| | - Yoshiyuki Takahashi
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, 466-8650, Japan
| | - Seiji Kojima
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, 466-8650, Japan
| | - Toshiyuki Fukao
- Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| |
Collapse
|
20
|
Zhang YL, Deng CX, Zhou WF, Zhou LY, Cao QQ, Shen WY, Liang H, Chen ZF. Synthesis and in vitro antitumor activity evaluation of copper(II) complexes with 5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline derivatives. J Inorg Biochem 2019; 201:110820. [DOI: 10.1016/j.jinorgbio.2019.110820] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/16/2019] [Accepted: 09/01/2019] [Indexed: 02/07/2023]
|
21
|
piggyBac Transposon-Based Immortalization of Human Deciduous Tooth Dental Pulp Cells with Multipotency and Non-Tumorigenic Potential. Int J Mol Sci 2019; 20:ijms20194904. [PMID: 31623314 PMCID: PMC6801629 DOI: 10.3390/ijms20194904] [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: 07/26/2019] [Revised: 09/21/2019] [Accepted: 09/30/2019] [Indexed: 12/14/2022] Open
Abstract
We aimed to immortalize primarily isolated human deciduous tooth-derived dental pulp cells (HDDPCs) by transfection with piggyBac (PB)-based transposon vectors carrying E7 from human papilloma virus 16 or complementary DNA (cDNA) encoding human telomerase reverse transcriptase (hTERT). HDDPCs were co-transfected with pTrans (conferring PB transposase expression) + pT-pac (conferring puromycin acetyltransferase expression) + pT-tdTomato (conferring tdTomato cDNA expression) and pT-E7 (conferring E7 expression) or pTrans + pT-pac + pT-EGFP (conferring enhanced green fluorescent protein cDNA expression) + pT-hTERT (conferring hTERT expression). After six days, these cells were selected in medium containing 5 μg/mL puromycin for one day, and then cultured in normal medium allowing cell survival. All resultant colonies were harvested and propagated as a pool. Stemness and tumorigenic properties of the established cell lines (“MT_E7” for E7 and “MT_hTERT” for hTERT) with untransfected parental cells (MT) were examined. Both lines exhibited proliferation similar to that of MT, with alkaline phosphatase activity and stemness-specific factor expression. They displayed differentiation potential into multi-lineage cells with no tumorigenic property. Overall, we successfully obtained HDDPC-derived immortalized cell lines using a PB-based transfection system. The resultant and parental cells were indistinguishable. Thus, E7 and hTERT could immortalize HDDPCs without causing cancer-associated changes or altering phenotypic properties.
Collapse
|
22
|
The duck EB66® cell substrate reveals a novel retrotransposon. Biologicals 2019; 61:22-31. [DOI: 10.1016/j.biologicals.2019.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 07/31/2019] [Accepted: 08/02/2019] [Indexed: 11/18/2022] Open
|
23
|
Abstract
Many recent advances have emerged in the telomere and telomerase fields. This Timeline article highlights the key advances that have expanded our views on the mechanistic underpinnings of telomeres and telomerase and their roles in ageing and disease. Three decades ago, the classic view was that telomeres protected the natural ends of linear chromosomes and that telomerase was a specific telomere-terminal transferase necessary for the replication of chromosome ends in single-celled organisms. While this concept is still correct, many diverse fields associated with telomeres and telomerase have substantially matured. These areas include the discovery of most of the key molecular components of telomerase, implications for limits to cellular replication, identification and characterization of human genetic disorders that result in premature telomere shortening, the concept that inhibiting telomerase might be a successful therapeutic strategy and roles for telomeres in regulating gene expression. We discuss progress in these areas and conclude with challenges and unanswered questions in the field.
Collapse
Affiliation(s)
- Jerry W Shay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA.
| | - Woodring E Wright
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| |
Collapse
|
24
|
Enhanced cardiac repair by telomerase reverse transcriptase over-expression in human cardiac mesenchymal stromal cells. Sci Rep 2019; 9:10579. [PMID: 31332256 PMCID: PMC6646304 DOI: 10.1038/s41598-019-47022-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 07/08/2019] [Indexed: 12/11/2022] Open
Abstract
We have previously reported a subpopulation of mesenchymal stromal cells (MSCs) within the platelet-derived growth factor receptor-alpha (PDGFRα)/CD90 co-expressing cardiac interstitial and adventitial cell fraction. Here we further characterise PDGFRα/CD90-expressing cardiac MSCs (PDGFRα + cMSCs) and use human telomerase reverse transcriptase (hTERT) over-expression to increase cMSCs ability to repair the heart after induced myocardial infarction. hTERT over-expression in PDGFRα + cardiac MSCs (hTERT + PDGFRα + cMSCs) modulates cell differentiation, proliferation, survival and angiogenesis related genes. In vivo, transplantation of hTERT + PDGFRα + cMSCs in athymic rats significantly increased left ventricular function, reduced scar size, increased angiogenesis and proliferation of both cardiomyocyte and non-myocyte cell fractions four weeks after myocardial infarction. In contrast, transplantation of mutant hTERT + PDGFRα + cMSCs (which generate catalytically-inactive telomerase) failed to replicate this cardiac functional improvement, indicating a telomerase-dependent mechanism. There was no hTERT + PDGFRα + cMSCs engraftment 14 days after transplantation indicating functional improvement occurred by paracrine mechanisms. Mass spectrometry on hTERT + PDGFRα + cMSCs conditioned media showed increased proteins associated with matrix modulation, angiogenesis, cell proliferation/survival/adhesion and innate immunity function. Our study shows that hTERT can activate pro-regenerative signalling within PDGFRα + cMSCs and enhance cardiac repair after myocardial infarction. An increased understanding of hTERT’s role in mesenchymal stromal cells from various organs will favourably impact clinical regenerative and anti-cancer therapies.
Collapse
|
25
|
Anitha A, Thanseem I, Vasu MM, Viswambharan V, Poovathinal SA. Telomeres in neurological disorders. Adv Clin Chem 2019; 90:81-132. [PMID: 31122612 DOI: 10.1016/bs.acc.2019.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ever since their discovery, the telomeres and the telomerase have been topics of intensive research, first as a mechanism of cellular aging and later as an indicator of health and diseases in humans. By protecting the chromosome ends, the telomeres play a vital role in preserving the information in our genome. Telomeres shorten with age and the rate of telomere erosion provides insight into the proliferation history of cells. The pace of telomere attrition is known to increase at the onset of several pathological conditions. Telomere shortening has been emerging as a potential contributor in the pathogenesis of several neurological disorders including autism spectrum disorders (ASD), schizophrenia, Alzheimer's disease (AD), Parkinson's disease (PD) and depression. The rate of telomere attrition in the brain is slower than that of other tissues owing to the low rate of cell proliferation in brain. Telomere maintenance is crucial for the functioning of stem cells in brain. Taking together the studies on telomere attrition in various neurological disorders, an association between telomere shortening and disease status has been demonstrated in schizophrenia, AD and depression, in spite of a few negative reports. But, studies in ASD and PD have failed to produce conclusive results. The cause-effect relationship between TL and neurological disorders is yet to be elucidated. The factors responsible for telomere erosion, which have also been implicated in the pathogenesis of neurological disorders, need to be explored in detail. Telomerase activation is now being considered as a potential therapeutic strategy for neurological disorders.
Collapse
Affiliation(s)
- Ayyappan Anitha
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India.
| | - Ismail Thanseem
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Mahesh Mundalil Vasu
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Vijitha Viswambharan
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Suresh A Poovathinal
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| |
Collapse
|
26
|
Herrera FE, Sferco SJ. Human telomerase protein: Understanding how the catalytic activity is suppressed under single substitutions of some conserved residues. A computational study. Proteins 2018; 86:1020-1036. [DOI: 10.1002/prot.25573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 06/05/2018] [Accepted: 06/22/2018] [Indexed: 12/28/2022]
Affiliation(s)
- Fernando E. Herrera
- Physics Department, Facultad de Bioquímica y Ciencias Biológicas; Universidad Nacional del Litoral. Ciudad Universitaria; Santa Fe Argentina
| | - Silvano J. Sferco
- Physics Department, Facultad de Bioquímica y Ciencias Biológicas; Universidad Nacional del Litoral. Ciudad Universitaria; Santa Fe Argentina
- Instituto de Física del Litoral (IFIS Litoral, UNL-CONICET); Santa Fe Argentina
| |
Collapse
|
27
|
Leão R, Apolónio JD, Lee D, Figueiredo A, Tabori U, Castelo-Branco P. Mechanisms of human telomerase reverse transcriptase (hTERT) regulation: clinical impacts in cancer. J Biomed Sci 2018. [PMID: 29526163 PMCID: PMC5846307 DOI: 10.1186/s12929-018-0422-8] [Citation(s) in RCA: 150] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background Limitless self-renewal is one of the hallmarks of cancer and is attained by telomere maintenance, essentially through telomerase (hTERT) activation. Transcriptional regulation of hTERT is believed to play a major role in telomerase activation in human cancers. Main body The dominant interest in telomerase results from its role in cancer. The role of telomeres and telomere maintenance mechanisms is well established as a major driving force in generating chromosomal and genomic instability. Cancer cells have acquired the ability to overcome their fate of senescence via telomere length maintenance mechanisms, mainly by telomerase activation. hTERT expression is up-regulated in tumors via multiple genetic and epigenetic mechanisms including hTERT amplifications, hTERT structural variants, hTERT promoter mutations and epigenetic modifications through hTERT promoter methylation. Genetic (hTERT promoter mutations) and epigenetic (hTERT promoter methylation and miRNAs) events were shown to have clinical implications in cancers that depend on hTERT activation. Knowing that telomeres are crucial for cellular self-renewal, the mechanisms responsible for telomere maintenance have a crucial role in cancer diseases and might be important oncological biomarkers. Thus, rather than quantifying TERT expression and its correlation with telomerase activation, the discovery and the assessment of the mechanisms responsible for TERT upregulation offers important information that may be used for diagnosis, prognosis, and treatment monitoring in oncology. Furthermore, a better understanding of these mechanisms may promote their translation into effective targeted cancer therapies. Conclusion Herein, we reviewed the underlying mechanisms of hTERT regulation, their role in oncogenesis, and the potential clinical applications in telomerase-dependent cancers.
Collapse
Affiliation(s)
- Ricardo Leão
- Division of Urology, Department of Surgery Princess Margaret Cancer Centre, University Health Network, 610 University Ave 3-130, Toronto, ON, M5G 2M9, Canada. .,Arthur and Sonia Labatt Brain Tumor Research Center, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada. .,Faculty of Medicine, University of Coimbra, R. Larga, 3004-504, Coimbra, Coimbra, Portugal. .,Department of Urology, Coimbra University Hospital, Coimbra, Portugal.
| | - Joana Dias Apolónio
- Regenerative Medicine Program, Department of Biomedical Sciences and Medicine, University of Algarve, Edifício 2 - Ala Norte, 8005-139, Faro, Portugal.,Centre for Biomedical Research (CBMR), University of Algarve, Faro, Portugal.,Algarve Biomedical Center, Campus Gambelas, Faro, Portugal
| | - Donghyun Lee
- Arthur and Sonia Labatt Brain Tumor Research Center, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Arnaldo Figueiredo
- Faculty of Medicine, University of Coimbra, R. Larga, 3004-504, Coimbra, Coimbra, Portugal.,Department of Urology, Coimbra University Hospital, Coimbra, Portugal
| | - Uri Tabori
- Arthur and Sonia Labatt Brain Tumor Research Center, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.,Division of Haematology/Oncology, The Hospital for Sick Children, 555 University Avenue, Toronto, M5G 1X8ON, Canada
| | - Pedro Castelo-Branco
- Regenerative Medicine Program, Department of Biomedical Sciences and Medicine, University of Algarve, Edifício 2 - Ala Norte, 8005-139, Faro, Portugal.,Centre for Biomedical Research (CBMR), University of Algarve, Faro, Portugal.,Algarve Biomedical Center, Campus Gambelas, Faro, Portugal
| |
Collapse
|
28
|
Current Perspectives of Telomerase Structure and Function in Eukaryotes with Emerging Views on Telomerase in Human Parasites. Int J Mol Sci 2018; 19:ijms19020333. [PMID: 29364142 PMCID: PMC5855555 DOI: 10.3390/ijms19020333] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 01/10/2018] [Accepted: 01/17/2018] [Indexed: 12/11/2022] Open
Abstract
Replicative capacity of a cell is strongly correlated with telomere length regulation. Aberrant lengthening or reduction in the length of telomeres can lead to health anomalies, such as cancer or premature aging. Telomerase is a master regulator for maintaining replicative potential in most eukaryotic cells. It does so by controlling telomere length at chromosome ends. Akin to cancer cells, most single-cell eukaryotic pathogens are highly proliferative and require persistent telomerase activity to maintain constant length of telomere and propagation within their host. Although telomerase is key to unlimited cellular proliferation in both cases, not much was known about the role of telomerase in human parasites (malaria, Trypanosoma, etc.) until recently. Since telomerase regulation is mediated via its own structural components, interactions with catalytic reverse transcriptase and several factors that can recruit and assemble telomerase to telomeres in a cell cycle-dependent manner, we compare and discuss here recent findings in telomerase biology in cancer, aging and parasitic diseases to give a broader perspective of telomerase function in human diseases.
Collapse
|
29
|
Frink RE, Peyton M, Schiller JH, Gazdar AF, Shay JW, Minna JD. Telomerase inhibitor imetelstat has preclinical activity across the spectrum of non-small cell lung cancer oncogenotypes in a telomere length dependent manner. Oncotarget 2017; 7:31639-51. [PMID: 27192120 PMCID: PMC5077965 DOI: 10.18632/oncotarget.9335] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 04/27/2016] [Indexed: 11/25/2022] Open
Abstract
Telomerase was evaluated as a therapeutic oncotarget by studying the efficacy of the telomerase inhibitor imetelstat in non-small cell lung cancer (NSCLC) cell lines to determine the range of response phenotypes and identify potential biomarkers of response. A panel of 63 NSCLC cell lines was studied for telomere length and imetelstat efficacy in inhibiting colony formation and no correlation was found with patient characteristics, tumor histology, and oncogenotypes. While there was no overall correlation between imetelstat efficacy with initial telomere length (ranging from 1.5 to 20 kb), the quartile of NSCLC lines with the shortest telomeres was more sensitive than the quartile with the longest telomeres. Continuous long-term treatment with imetelstat resulted in sustained telomerase inhibition, progressive telomere shortening and eventual growth inhibition in a telomere-length dependent manner. Cessation of imetelstat therapy before growth inhibition was followed by telomere regrowth. Likewise, in vivo imetelstat treatment caused tumor xenograft growth inhibition in a telomere-length dependent manner. We conclude from these preclinical studies of telomerase as an oncotarget tested by imetelstat response that imetelstat has efficacy across the entire oncogenotype spectrum of NSCLC, continuous therapy is necessary to prevent telomere regrowth, and short telomeres appears to be the best treatment biomarker.
Collapse
Affiliation(s)
- Robin E Frink
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Michael Peyton
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joan H Schiller
- Inova Schar Cancer Institute, Falls Church, VA, USA.,Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Adi F Gazdar
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jerry W Shay
- Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Center for Excellence in Genomics Medicine Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - John D Minna
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| |
Collapse
|
30
|
Thanseem I, Viswambharan V, Poovathinal SA, Anitha A. Is telomere length a biomarker of neurological disorders? Biomark Med 2017; 11:799-810. [PMID: 30669856 DOI: 10.2217/bmm-2017-0032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Telomeres are DNA-protein complexes that form protective caps at the termini of chromosomes, maintaining genomic stability. In this review, we provide a comprehensive overview on the usefulness of telomere length (TL) as biomarkers of neurological disorders. The implications of TL in relation to cognitive ability, cognitive aging and cognitive decline in neurodegenerative disorders are also briefly discussed. Our review suggests that at present it is difficult to draw a reliable conclusion regarding the contribution of TL to neurological disorders. Further, it needs to be examined whether leukocyte TL, which is generally considered as a surrogate marker of TL in other tissues, serves as an indicator of central nervous system TL.
Collapse
Affiliation(s)
- Ismail Thanseem
- Department of Neurogenetics, Institute for Communicative & Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Vijitha Viswambharan
- Department of Neurogenetics, Institute for Communicative & Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Suresh A Poovathinal
- Department of Neurology, Institute for Communicative & Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| | - Ayyappan Anitha
- Department of Neurogenetics, Institute for Communicative & Cognitive Neurosciences (ICCONS), Shoranur, Palakkad 679 523, Kerala, India
| |
Collapse
|
31
|
Hoekstra R, Deurholt T, ten Bloemendaal L, Desille M, van Wijk ACWA, Clement B, Oude Elferink RPJ, van Gulik TM, Chamuleau RAFM. Assessment of in Vitro Applicability of Reversibly Immortalized NKNT-3 Cells and Clonal Derivatives. Cell Transplant 2017; 15:423-433. [DOI: 10.3727/000000006783981873] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In vitro applications of human hepatocytes, such as bioartificial livers and toxicity assays, require thoroughly testing of human cell lines prior to using them as alternative cell sources. The reversibly immortalized NKNT-3 cell line was reported to show clear in vivo functionality. Here, NKNT-3 cells were tested for their in vitro applicability. Low-passage (P2) and high-passage (P28) NKNT-3 cells and clonal derivatives were characterized for reversion of immortalization, heterogeneity, and hepatic functionality. Reversion with reduced expression of immortalizing agent could be established. However, during culturing the cells lost the capacity to be selected for completed reversion. The phenotypic instability is probably associated with heterogeneity in the culture, as clonal derivatives of P2 cells varied in morphology, growth, and reversion characteristics. The mRNA levels of genes related with hepatic differentiation increased 4–20-fold after reversion. However, the levels never exceeded 0.1% of that detected in liver and no urea production nor ammonia elimination was detected. Additionally, activities of different cytochrome P450s were limited. In conclusion, the NKNT-3 culture is heterogeneous and unstable and the in vitro functionality is relatively low. These findings emphasize that in vivo testing of hepatic cell lines is little informative for predicting their value for in vitro applications.
Collapse
Affiliation(s)
- Ruurdtje Hoekstra
- Surgical Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
- AMC Liver Center, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Tanja Deurholt
- AMC Liver Center, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Lysbeth ten Bloemendaal
- Surgical Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
- AMC Liver Center, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Mireille Desille
- INSERM U456, Detoxication and Tissue Repair Unit, University of Rennes I, Rennes, France
| | | | - Bruno Clement
- INSERM U456, Detoxication and Tissue Repair Unit, University of Rennes I, Rennes, France
| | | | - Thomas M. van Gulik
- Surgical Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
| | | |
Collapse
|
32
|
Lai AG, Pouchkina-Stantcheva N, Di Donfrancesco A, Kildisiute G, Sahu S, Aboobaker AA. The protein subunit of telomerase displays patterns of dynamic evolution and conservation across different metazoan taxa. BMC Evol Biol 2017; 17:107. [PMID: 28441946 PMCID: PMC5405514 DOI: 10.1186/s12862-017-0949-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 04/04/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Most animals employ telomerase, which consists of a catalytic subunit known as the telomerase reverse transcriptase (TERT) and an RNA template, to maintain telomere ends. Given the importance of TERT and telomere biology in core metazoan life history traits, like ageing and the control of somatic cell proliferation, we hypothesised that TERT would have patterns of sequence and regulatory evolution reflecting the diverse life histories across the Animal Kingdom. RESULTS We performed a complete investigation of the evolutionary history of TERT across animals. We show that although TERT is almost ubiquitous across Metazoa, it has undergone substantial sequence evolution within canonical motifs. Beyond the known canonical motifs, we also identify and compare regions that are highly variable between lineages, but show conservation within phyla. Recent data have highlighted the importance of alternative splice forms of TERT in non-canonical functions and although animals may share some conserved introns, we find that the selection of exons for alternative splicing appears to be highly variable, and regulation by alternative splicing appears to be a very dynamic feature of TERT evolution. We show that even within a closely related group of triclad flatworms, where alternative splicing of TERT was previously correlated with reproductive strategy, we observe highly diverse splicing patterns. CONCLUSIONS Our work establishes that the evolutionary history and structural evolution of TERT involves previously unappreciated levels of change and the emergence of lineage specific motifs. The sequence conservation we describe within phyla suggests that these new motifs likely serve essential biological functions of TERT, which along with changes in splicing, underpin diverse functions of TERT important for animal life histories.
Collapse
Affiliation(s)
- Alvina G Lai
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
| | | | | | - Gerda Kildisiute
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - Sounak Sahu
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - A Aziz Aboobaker
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK.
| |
Collapse
|
33
|
Waghorn PA, Jackson MR, Gouverneur V, Vallis KA. Targeting telomerase with radiolabeled inhibitors. Eur J Med Chem 2017; 125:117-129. [PMID: 27657809 PMCID: PMC5154340 DOI: 10.1016/j.ejmech.2016.09.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 09/08/2016] [Accepted: 09/09/2016] [Indexed: 12/22/2022]
Abstract
The expression of telomerase in approximately 85% of cancers and its absence in the majority of normal cells makes it an attractive target for cancer therapy. However the lag period between initiation of telomerase inhibition and growth arrest makes direct inhibition alone an insufficient method of treatment. However, telomerase inhibition has been shown to enhance cancer cell radiosensitivity. To investigate the strategy of simultaneously inhibiting telomerase while delivering targeted radionuclide therapy to cancer cells, 123I-radiolabeled inhibitors of telomerase were synthesized and their effects on cancer cell survival studied. An 123I-labeled analogue of the telomerase inhibitor MST-312 inhibited telomerase with an IC50 of 1.58 μM (MST-312 IC50: 0.23 μM). Clonogenic assays showed a dose dependant effect of 123I-MST-312 on cell survival in a telomerase positive cell line, MDA-MB-435.
Collapse
Affiliation(s)
- Philip A Waghorn
- CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Off Roosevelt Drive, Oxford, OX3 7DQ, UK.
| | - Mark R Jackson
- CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Off Roosevelt Drive, Oxford, OX3 7DQ, UK.
| | - Veronique Gouverneur
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Katherine A Vallis
- CR-UK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Off Roosevelt Drive, Oxford, OX3 7DQ, UK.
| |
Collapse
|
34
|
Benedetti R, Dell’Aversana C, Giorgio C, Astorri R, Altucci L. Breast Cancer Vaccines: New Insights. Front Endocrinol (Lausanne) 2017; 8:270. [PMID: 29081765 PMCID: PMC5645504 DOI: 10.3389/fendo.2017.00270] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 09/26/2017] [Indexed: 01/07/2023] Open
Abstract
Breast cancer (BC) is a persistent global challenge for its high frequency in women (although it seldom occurs in men), due to the large diffusion of risk factors and gene mutations, and for its peculiar biology and microenvironment. To date, BC can benefit from different therapeutic strategies involving surgery, ablation, chemotherapy, radiotherapy, and more specific approaches such as hormone therapy and the administration of various substances impairing cancer growth, aggressivity, and recurrence with different modalities. Despite these relatively wide chances, also used in combinatory protocols, relevant mortality and relapse rates, often associated with resistant phenotypes, stress the need for a personalized-medicine based on prompting the patient's immune system (IS) against cancer cells. BC immunogenicity was latterly proven, so the whole immunotherapy field for BC is still at a very early stage. This immunotherapeutic approach exploits both the high specificity of adaptive immune response and the immunological memory. This review is focused on some of the majorly relevant BC vaccines available (NeuVax, AVX901, and INO-1400), providing a description of the more promising clinical trials. The efficacy of cancer vaccines highly depends on the patient's IS, and a wide optimization is needed in terms of targets' selection, drug design and combinations, dose finding, protocol structuring, and patients' recruitment; moreover, new standards are being discussed for the outcome evaluation. However, early-phases excellent results suggest that the manipulation of the IS via specific vaccines is a highly attractive approach for BC.
Collapse
Affiliation(s)
- Rosaria Benedetti
- Dipartimento di Biochimica Biofisica e Patologia generale, Università degli Studi della Campania ‘L. Vanvitelli’ Naples, Naples, Italy
- *Correspondence: Rosaria Benedetti, ; Lucia Altucci,
| | - Carmela Dell’Aversana
- Dipartimento di Biochimica Biofisica e Patologia generale, Università degli Studi della Campania ‘L. Vanvitelli’ Naples, Naples, Italy
| | - Cristina Giorgio
- Dipartimento di Biochimica Biofisica e Patologia generale, Università degli Studi della Campania ‘L. Vanvitelli’ Naples, Naples, Italy
| | - Roberta Astorri
- Dipartimento di Biochimica Biofisica e Patologia generale, Università degli Studi della Campania ‘L. Vanvitelli’ Naples, Naples, Italy
- Dipartimento di Medicina e Scienze della Salute “Vincenzo Tiberio”, Università degli Studi del Molise, Campobasso, Italy
| | - Lucia Altucci
- Dipartimento di Biochimica Biofisica e Patologia generale, Università degli Studi della Campania ‘L. Vanvitelli’ Naples, Naples, Italy
- *Correspondence: Rosaria Benedetti, ; Lucia Altucci,
| |
Collapse
|
35
|
Abstract
Telomerase activity is responsible for the maintenance of chromosome end structures (telomeres) and cancer cell immortality in most human malignancies, making telomerase an attractive therapeutic target. The rationale for targeting components of the telomerase holoenzyme has been strengthened by accumulating evidence indicating that these molecules have extra-telomeric functions in tumour cell survival and proliferation. This Review discusses current knowledge of the biogenesis, structure and multiple functions of telomerase-associated molecules intertwined with recent advances in drug discovery approaches. We also describe the fertile ground available for the pursuit of next-generation small-molecule inhibitors of telomerase.
Collapse
Affiliation(s)
- Greg M Arndt
- Australian Cancer Research Foundation (ACRF) Drug Discovery Centre for Childhood Cancer, Children's Cancer Institute Australia, Lowy Cancer Research Centre, University of New South Wales, Randwick, New South Wales 2031, Australia
| | - Karen L MacKenzie
- Personalised Medicine Program, Children's Cancer Institute Australia, Lowy Cancer Research Centre, University of New South Wales, Randwick, New South Wales 2031, Australia
| |
Collapse
|
36
|
Abstract
INTRODUCTION Telomerase is a ribonucleoprotein that catalyses the addition of telomeric repeat sequences (having the sequence 5'-TTAGGG-3' in humans) to the ends of chromosomes. Telomerase activity is detected in most types of human tumours, but it is almost undetectable in normal somatic cells. Therefore, telomerase is a promising therapeutic target. To date, the known inhibitors of telomerase include nucleoside analogues, oligonucleotides and G-quadruplex stabilizers. This review highlights recent advances in our understanding of telomerase inhibitors, the relationships between telomerase inhibitors, cancer, and fields such as inflammation. AREAS COVERED This review summarizes new patents published on telomerase inhibitors from 2010 to 2015. EXPERT OPINION The review provides a brief account of the background, development, and on-going issues involving telomerase inhibitors. In particular, this review emphasizes imetelstat (GRN163L) and some typical G-quadruplex stabilizers that participate in telomerase inhibition. Overall, the research scope of antineoplastic is becoming broader and telomerase inhibitors have been shown to be a promising therapeutic target. Therefore, novel antineoplastic agents with greater activity and higher specificity must be developed.
Collapse
Affiliation(s)
- Ruo-Jun Man
- a State Key Laboratory of Pharmaceutical Biotechnology , Nanjing University , Nanjing , People's Republic of China.,b Preparatory College Education , Guangxi University for Nationalities , Nanning , People's Republic of China
| | - Long-Wang Chen
- a State Key Laboratory of Pharmaceutical Biotechnology , Nanjing University , Nanjing , People's Republic of China
| | - Hai-Liang Zhu
- a State Key Laboratory of Pharmaceutical Biotechnology , Nanjing University , Nanjing , People's Republic of China
| |
Collapse
|
37
|
Servant G, Deininger PL. Insertion of Retrotransposons at Chromosome Ends: Adaptive Response to Chromosome Maintenance. Front Genet 2016; 6:358. [PMID: 26779254 PMCID: PMC4700185 DOI: 10.3389/fgene.2015.00358] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/10/2015] [Indexed: 01/30/2023] Open
Abstract
The telomerase complex is a specialized reverse transcriptase (RT) that inserts tandem DNA arrays at the linear chromosome ends and contributes to the protection of the genetic information in eukaryotic genomes. Telomerases are phylogenetically related to retrotransposons, encoding also the RT activity required for the amplification of their sequences throughout the genome. Intriguingly the telomerase gene is lost from the Drosophila genome and tandem retrotransposons replace telomeric sequences at the chromosome extremities. This observation suggests the versatility of RT activity in counteracting the chromosome shortening associated with genome replication and that retrotransposons can provide this activity in case of a dysfunctional telomerase. In this review paper, we describe the major classes of retroelements present in eukaryotic genomes in order to point out the differences and similarities with the telomerase complex. In a second part, we discuss the insertion of retroelements at the ends of chromosomes as an adaptive response for dysfunctional telomeres.
Collapse
Affiliation(s)
| | - Prescott L. Deininger
- Tulane Cancer Center, Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LAUSA
| |
Collapse
|
38
|
Zhang Y, Wu Y, Mao P, Li F, Han X, Zhang Y, Jiang S, Chen Y, Huang J, Liu D, Zhao Y, Ma W, Songyang Z. Cold-inducible RNA-binding protein CIRP/hnRNP A18 regulates telomerase activity in a temperature-dependent manner. Nucleic Acids Res 2015; 44:761-75. [PMID: 26673712 PMCID: PMC4737163 DOI: 10.1093/nar/gkv1465] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 12/01/2015] [Indexed: 01/22/2023] Open
Abstract
The telomerase is responsible for adding telomeric repeats to chromosomal ends and consists of the reverse transcriptase TERT and the RNA subunit TERC. The expression and activity of the telomerase are tightly regulated, and aberrant activation of the telomerase has been observed in >85% of human cancers. To better understand telomerase regulation, we performed immunoprecipitations coupled with mass spectrometry (IP-MS) and identified cold inducible RNA-binding protein (CIRP or hnRNP A18) as a telomerase-interacting factor. We have found that CIRP is necessary to maintain telomerase activities at both 32°C and 37°C. Furthermore, inhibition of CIRP by CRISPR-Cas9 or siRNA knockdown led to reduced telomerase activities and shortened telomere length, suggesting an important role of CIRP in telomere maintenance. We also provide evidence here that CIRP associates with the active telomerase complex through direct binding of TERC and regulates Cajal body localization of the telomerase. In addition, CIRP regulates the level of TERT mRNAs. At the lower temperature, TERT mRNA is upregulated in a CIRP-dependent manner to compensate for reduced telomerase activities. Taken together, these findings highlight the dual roles that CIRP plays in regulating TERT and TERC, and reveal a new class of telomerase modulators in response to hypothermia conditions.
Collapse
Affiliation(s)
- Youwei Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China Collaborative Innovation Center for Cancer Medicine, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Yangxiu Wu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Pingsu Mao
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Feng Li
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Xin Han
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yi Zhang
- Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Shuai Jiang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Yuxi Chen
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Junjiu Huang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Dan Liu
- Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Yong Zhao
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Wenbin Ma
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China Collaborative Innovation Center for Cancer Medicine, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Zhou Songyang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China Collaborative Innovation Center for Cancer Medicine, Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| |
Collapse
|
39
|
Huang Y, Sun L, Liu N, Wei Q, Jiang L, Tong X, Ye X. Polo-like Kinase 1 (Plk1) Up-regulates Telomerase Activity by Affecting Human Telomerase Reverse Transcriptase (hTERT) Stability. J Biol Chem 2015; 290:18865-73. [PMID: 26070557 PMCID: PMC4513140 DOI: 10.1074/jbc.m114.635375] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 06/11/2015] [Indexed: 12/13/2022] Open
Abstract
Maintenance of telomere is regulated by active telomerase complex, including telomerase holoenzyme and its associated proteins. The activity of telomerase is precisely controlled in cells, and its dysregulation is one of the hallmarks of cancer. The telomerase catalytic subunit human telomerase reverse transcriptase (hTERT) plays a central role for telomerase activity. In this study, we indentified that Polo-like kinase 1 (Plk1) is a novel telomerase-associated protein. Plk1 can interact with hTERT independently of its kinase activity. More importantly, we found that Plk1 is associated with active telomerase complex. In addition, we demonstrated that knockdown of Plk1 caused the reduction of telomerase activity, whereas overexpression of Plk1 increased telomerase activity. Further analysis showed that overexpression of Plk1 led to a significant increase of hTERT protein by prolonging its half-life but did not affect the level of hTERT mRNA. Furthermore, we found that Plk1 enhanced the chromatin loading of hTERT and inhibited its ubiquitination. This implied that Plk1 affected hTERT stability by inhibiting its ubiquitin-mediated degradation. Collectively, these observations suggested that Plk1 is a positive modulator of telomerase by enhancing the stability of hTERT.
Collapse
Affiliation(s)
- Yan Huang
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and the University of Chinese Academy of Sciences, Beijing 100101, China
| | - Liping Sun
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and the University of Chinese Academy of Sciences, Beijing 100101, China
| | - Ningning Liu
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and the University of Chinese Academy of Sciences, Beijing 100101, China
| | - Qian Wei
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and the University of Chinese Academy of Sciences, Beijing 100101, China
| | - Liangzhen Jiang
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and the University of Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaomei Tong
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and
| | - Xin Ye
- From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS) and
| |
Collapse
|
40
|
Mizukoshi E, Nakagawa H, Kitahara M, Yamashita T, Arai K, Sunagozaka H, Fushimi K, Kobayashi E, Kishi H, Muraguchi A, Kaneko S. Immunological features of T cells induced by human telomerase reverse transcriptase-derived peptides in patients with hepatocellular carcinoma. Cancer Lett 2015; 364:98-105. [PMID: 25982205 DOI: 10.1016/j.canlet.2015.04.031] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 04/13/2015] [Accepted: 04/14/2015] [Indexed: 01/04/2023]
Abstract
Human telomerase reverse transcriptase (hTERT) is a catalytic enzyme required for telomere elongation. In this study, we investigated the safety and immunogenicity of an hTERT-derived peptide (hTERT461) as a vaccine and characterized the hTERT-specific T cell responses induced. Fourteen hepatocellular carcinoma (HCC) patients were enrolled in the study. The hTERT-derived peptide was emulsified in incomplete Freund's adjuvant and administered via subcutaneous immunization three times biweekly. The maximum toxicity observed was grade 2 according to the common terminology criteria and mainly consisted of skin reactions at the site of vaccination. The vaccination induced hTERT-specific immunity in 71.4% of patients and 57.1% of patients administered with hTERT461 peptide-specific T cells could prevent HCC recurrence after vaccination. In phenotypic analysis, the post-vaccinated increase in hTERT-specific T cells was due to an increase in cells with the effector memory phenotype, with the potential to produce multiple cytokines. Seven hTERT-specific T cell receptors were obtained from the vaccinated patients, showing their cytotoxic activities to hTERT-derived peptide-bearing cells. In conclusion, the safety and effects of immune boosting by hTERT461 peptide have shown the potential of the peptide to provide clinical benefits in HCC patients.
Collapse
Affiliation(s)
- Eishiro Mizukoshi
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Hidetoshi Nakagawa
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Masaaki Kitahara
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Tatsuya Yamashita
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Kuniaki Arai
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Hajime Sunagozaka
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Kazumi Fushimi
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan
| | - Eiji Kobayashi
- Department of Immunology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Hiroyuki Kishi
- Department of Immunology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Atsushi Muraguchi
- Department of Immunology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Shuichi Kaneko
- Department of Gastroenterology, Graduate School of Medicine, Kanazawa University, Kanazawa, Japan.
| |
Collapse
|
41
|
Giri S, Bader A. Immortalization of Human Fetal Hepatocyte by Ectopic Expression of Human Telomerase Reverse Transcriptase, Human Papilloma Virus (E7) and Simian Virus 40 Large T (SV40 T) Antigen Towards Bioartificial Liver Support. J Clin Exp Hepatol 2014; 4:191-201. [PMID: 25755560 PMCID: PMC4284290 DOI: 10.1016/j.jceh.2014.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 08/14/2014] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Generation of genetically stable and non-tumoric immortalization cell line from primary cells would be enormously useful for research and therapeutic purposes, but progress towards this goal has so far been limited. It is now universal acceptance that immortalization of human fetal hepatocytes based on recent advances of telomerase biology and oncogene, lead to unlimited population doubling could be the possible source for bioartificial liver device. METHODS Immortalization of human fetal hepatocytes cell line by ectopic expression of human telomerase reverse transcriptase (hTERT), human papilloma virus gene (E7) and simian virus 40 large T (SV40 T) antigens is main goal of present study. We used an inducible system containing human telomerase and E7, both of which are cloned into responder constructs controlled by doxycycline transactivator. We characterized the immortalized human fetal hepatocyte cells by analysis of green fluorescent cells (GFP) positive cells using flow cytometry (FACs) cell sorting and morphology, proliferative rate and antigen expression by immunohistochemical analysis. In addition to we analysized lactate formation, glucose consumption, albumin secretion and urea production of immortalized human fetal hepatocyte cells. RESULTS After 25 attempts for transfection of adult primary hepatocytes by human telomerase and E7 to immortalize them, none of the transfection systems resulted in the production of a stable, proliferating cell line. Although the transfection efficiency was more than 70% on the first day, the vast majority of the transfected hepatocytes lost their signal within the first 5-7 days. The remaining transfected hepatocytes persisted for 2-4 weeks and divided one or two times without forming a clone. After 10 attempts of transfection human fetal hepatocytes using the same transfection system, we obtained one stable human fetal hepatocytes cell line which was able albumin secretion urea production and glucose consumption. CONCLUSION We established a conditional human fetal hepatocytes cell line with mesenchymal characteristics. Thus immortalization of human fetal hepatocytes cell line by telomerase biology offers a great challenge to examine basic biological mechanisms which are directly related to human and best cell source having unlimited population doubling for bioartificial support without any risk of replicative senescence and pathogenic risks.
Collapse
Key Words
- AFP, alpha-fetoprotein
- BLD, bioartificail liver device
- E7
- E7, human papilloma virus
- EBV, epstein barr virus
- EGFP, enhanced green fluorescent protein
- FACs, flow cytometry
- FH, fetal hepatocytes
- GFP, green fluorescent cells positive cells
- HPV, human papilloma virus
- SV T 40 antigen
- SV40 T, simian virus 40 large T
- bioartificial liver device
- hTERT
- hTERT, human telomerase reverse transcriptase
- human fetal hepatocytes
- iPS, pluripotent stem cell
Collapse
Affiliation(s)
- Shibashish Giri
- Address for correspondence: Shibashish Giri, Department of Cell Techniques and Applied Stem Cell Biology, Center for Biotechnology and Biomedicine (BBZ), Medical Faculty, University of Leipzig, Leipzig, Germany. Tel.: +49 341 9731353; fax: +49 341 9731329.
| | | |
Collapse
|
42
|
Chuanwu Z, Feng Q, Ming L, Haiyan W, Huan F, Xiangrong L, Xuehua Z, Xiang Z, Xiujuan S, Ping X. Detection of telomerase reverse transcriptase mRNA in peripheral blood mononuclear cells of patients with liver failure. HEPATITIS MONTHLY 2014; 14:e17976. [PMID: 24829587 PMCID: PMC4013496 DOI: 10.5812/hepatmon.17976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 02/21/2014] [Accepted: 03/12/2014] [Indexed: 12/11/2022]
Abstract
BACKGROUND Telomerase activity is closely associated with the expression of human telomerase reverse transcriptase (hTERT) mRNA; although it can be induced in hepatocytes during liver regeneration, its dynamic change in patients with liver failure has remained unclear. OBJECTIVES We investigated the variation and significance of hTERT mRNA expression in peripheral blood mononuclear cells (PBMCs) of the patients with liver failure. PATIENTS AND METHODS In this clinical experimental study, 76 Chinese patients were enrolled in the study between 2010 and 2012. The level of PBMCs hTERT mRNA was detected by relative quantitative real-time polymerase chain reaction (RT-PCR) in the samples taken before treatment and at seven-day intervals during a 28-day treatment period. The patients were divided into survivor and non-survivor groups according to the 3-months mortality after treatment. The dynamic variation of PBMCs hTERT mRNA was analyzed and its association with prognosis was assessed by the area under the receiver-operating characteristic curve. RESULTS The median level of PBMCs hTERT mRNA in survivors increased with treatment time and was significantly higher than the corresponding level in non-survivors after 14 days of treatment (P < 0.001). Subgroup analyses showed that the levels of PBMCs hTERT mRNA were remarkably higher in patients with acute-on-chronic liver failure than in those with chronic liver failure (P < 0.05). In patients with the same clinical type of liver failure, the level was markedly higher in survivors than in non-survivors after 14 days of treatment (P < 0.05); however, the levels were not significantly different between subgroups with different clinical type but the same prognosis. The sensitivity and specificity of PBMCs hTERT mRNA was high in evaluating the prognosis at day 14 and became much higher at days 21 and 28 post treatment. The expression of PBMCs hTERT mRNA had high sensitivity and specificity in evaluating the prognosis as early as day 14 post treatment and was significantly superior to the prognostic value of serum alpha-fetoprotein. CONCLUSIONS The expression of PBMCs hTERT mRNA is closely associated with patient outcome, which indicates that hTERT mRNA in PBMCs might be useful as a prognostic biomarker of liver failure.
Collapse
Affiliation(s)
- Zhu Chuanwu
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
- Corresponding Author: Zhu Chuanwu, Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China. Tel: +86-51265180193, Fax: +86-51265291020, E-mail:
| | - Qian Feng
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Li Ming
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Wang Haiyan
- Department of Infectious Diseases, The Second Affiliated Hospital of Bengbu Medical College, Bengbu, China
| | - Fang Huan
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Luo Xiangrong
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Zhang Xuehua
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Zhu Xiang
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Shen Xiujuan
- Department of Hepatology, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| | - Xu Ping
- Key Laboratory of Infection and Immunity, The Affiliated Infectious Disease Hospital of Soochow University, Suzhou, China
| |
Collapse
|
43
|
Alternative lengthening of telomeres in cancer stem cells in vivo. Oncogene 2014; 34:611-20. [PMID: 24531712 PMCID: PMC4135038 DOI: 10.1038/onc.2013.603] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 11/01/2013] [Accepted: 12/18/2013] [Indexed: 12/17/2022]
Abstract
Chromosome ends are protected by telomeres which prevent DNA damage response and degradation. Telomerase expression extends telomeres and inhibits DNA damage response. Telomeres are also maintained by the recombination based alternative lengthening pathway. Telomerase is believed to be the sole mechanism for telomere maintenance in epidermis. We show that basal cells in epidermis maintain telomeres both by telomerase and ALT mechanisms in vivo. ALT was detected in epidermal stem cells in Terc−/− mice, and normal human epidermal keratinocytes are also ALT positive. ALT pathway is suppressed in primary but not metastatic epidermal squamous cell carcinomas (SCC) in Terc+/+ mice. ALT pathway is expressed in stem and basal cells in epidermal SCC in Terc−/− mice, and some telomerase positive human SCC lines. Telomeres shorten dramatically in stem and basal cells in epidermal SCC in vivo. Telomere shortening is associated with telomeric DNA damage response and apoptosis in stem and basal cells. Stem cells were transformed in both primary and metastatic epidermal SCC. Genetic ablation of this small cell population resulted in significant tumor regression in vivo. We concluded that alternative lengthening of telomeres is important in epidermal homeostasis and tumorigenesis in vivo.
Collapse
|
44
|
Wang WL, Yeh YT, Chen LJ, Chiu JJ. Regulation of fibrillar collagen-mediated smooth muscle cell proliferation in response to chemical stimuli by telomere reverse transcriptase through c-Myc. Biomaterials 2014; 35:3829-39. [PMID: 24508371 DOI: 10.1016/j.biomaterials.2014.01.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 01/21/2014] [Indexed: 11/25/2022]
Abstract
Human telomerase reverse transcriptase (hTERT) and oncogene c-Myc have been shown to regulate cell proliferation. Our previous studies demonstrated that fibrillar collagen mediates vascular smooth muscle cell (SMC) cycle progression and proliferation in response to platelet-derived growth factor (PDGF)-BB and interleukin (IL)-1β. However, whether hTERT and c-Myc are involved in these fibrillar collagen-mediated SMC responses remain unclear. The present study elucidated the regulatory role of hTERT and c-Myc in PDGF-BB/IL-1β-induced cell cycle progression in SMCs on fibrillar collagen and its underlying mechanisms. Our results showed that PDGF-BB and IL-1β exert synergistic effects to induce hTERT expression, but not its activity, in human arterial SMCs on fibrillar collagen. This PDGF-BB/IL-1β-induced up-regulation of hTERT contributes to cell cycle progression in SMCs through the up-regulation of cyclin-dependent kinase-6 and down-regulations of p27(KIP1) and p21(CIP1). In addition, PDGF-BB/IL-1β induces up-regulation of c-Myc in SMCs on fibrillar collagen; this response is mediated by the increased binding of hTERT, which can form complexes with TPP1 and hnRNPK, to the guanine-rich region of the c-Myc promoter and consequently contributes to cell cycle progression in SMCs on fibrillar collagen. Moreover, the PDGF-BB/IL-1β-induced hTERT and c-Myc expressions are regulated by phosphatidylinositol 3-kinase/Akt in SMCs on fibrillar collagen. Our findings provide insights into the mechanisms by which hTERT and c-Myc regulates SMC cell cycle progression and proliferation on fibrillar collagen in response to chemical stimuli.
Collapse
Affiliation(s)
- Wei-Li Wang
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli 350, Taiwan
| | - Yi-Ting Yeh
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli 350, Taiwan
| | - Li-Jing Chen
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli 350, Taiwan
| | - Jeng-Jiann Chiu
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli 350, Taiwan.
| |
Collapse
|
45
|
Wu XQ, Huang C, He X, Tian YY, Zhou DX, He Y, Liu XH, Li J. Feedback regulation of telomerase reverse transcriptase: new insight into the evolving field of telomerase in cancer. Cell Signal 2013; 25:2462-8. [DOI: 10.1016/j.cellsig.2013.08.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 08/23/2013] [Indexed: 01/07/2023]
|
46
|
Gansner JM, Rosas IO. Telomeres in lung disease. Transl Res 2013; 162:343-52. [PMID: 23618685 DOI: 10.1016/j.trsl.2013.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 04/02/2013] [Accepted: 04/03/2013] [Indexed: 12/16/2022]
Abstract
Telomeres are DNA-protein structures that cap the ends of chromosomes; telomerase is the enzyme that ensures their integrity. Telomere biology has recently been implicated in the pathogenesis of a variety of lung diseases, including idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease/emphysema, and lung cancer. This review highlights recent discoveries pertaining to the role of telomere biology in lung disease.
Collapse
Affiliation(s)
- John M Gansner
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
| | | |
Collapse
|
47
|
Morgan CC, Mc Cartney AM, Donoghue MTA, Loughran NB, Spillane C, Teeling EC, O'Connell MJ. Molecular adaptation of telomere associated genes in mammals. BMC Evol Biol 2013; 13:251. [PMID: 24237966 PMCID: PMC3833184 DOI: 10.1186/1471-2148-13-251] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 11/06/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Placental mammals display a huge range of life history traits, including size, longevity, metabolic rate and germ line generation time. Although a number of general trends have been proposed between these traits, there are exceptions that warrant further investigation. Species such as naked mole rat, human and certain bat species all exhibit extreme longevity with respect to body size. It has long been established that telomeres and telomere maintenance have a clear role in ageing but it has not yet been established whether there is evidence for adaptation in telomere maintenance proteins that could account for increased longevity in these species. RESULTS Here we carry out a molecular investigation of selective pressure variation, specifically focusing on telomere associated genes across placental mammals. In general we observe a large number of instances of positive selection acting on telomere genes. Although these signatures of selection overall are not significantly correlated with either longevity or body size we do identify positive selection in the microbat species Myotis lucifugus in functionally important regions of the telomere maintenance genes DKC1 and TERT, and in naked mole rat in the DNA repair gene BRCA1. CONCLUSION These results demonstrate the multifarious selective pressures acting across the mammal phylogeny driving lineage-specific adaptations of telomere associated genes. Our results show that regardless of the longevity of a species, these proteins have evolved under positive selection thereby removing increased longevity as the single selective force driving this rapid rate of evolution. However, evidence of molecular adaptations specific to naked mole rat and Myotis lucifugus highlight functionally significant regions in genes that may alter the way in which telomeres are regulated and maintained in these longer-lived species.
Collapse
|
48
|
Bollmann FM. Physiological and pathological significance of human telomerase reverse transcriptase splice variants. Biochimie 2013; 95:1965-70. [DOI: 10.1016/j.biochi.2013.07.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 07/29/2013] [Indexed: 12/22/2022]
|
49
|
Bosch-Presegué L, Vaquero A. Sirtuins in stress response: guardians of the genome. Oncogene 2013; 33:3764-75. [DOI: 10.1038/onc.2013.344] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 12/15/2022]
|
50
|
Yan J, Pankhong P, Shin TH, Obeng-Adjei N, Morrow MP, Walters JN, Khan AS, Sardesai NY, Weiner DB. Highly optimized DNA vaccine targeting human telomerase reverse transcriptase stimulates potent antitumor immunity. Cancer Immunol Res 2013; 1:179-189. [PMID: 24777680 DOI: 10.1158/2326-6066.cir-13-0001] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
High levels of human telomerase reverse transcriptase (hTERT) are detected in more than 85% of human cancers. Immunologic analysis supports that hTERT is a widely applicable target recognized by T cells and can be potentially studied as a broad cancer immunotherapeutic, or a unique line of defense against tumor recurrence. There remains an urgent need to develop more potent hTERT vaccines. Here, a synthetic highly optimized full-length hTERT DNA vaccine (phTERT) was designed and the induced immunity was examined in mice and non-human primates (NHP). When delivered by electroporation, phTERT elicited strong, broad hTERT-specific CD8 T-cell responses including induction of T cells expressing CD107a, IFN-γ, and TNF-α in mice. The ability of phTERT to overcome tolerance was evaluated in an NHP model, whose TERT is 96% homologous to that of hTERT. Immunized monkeys exhibited robust [average 1,834 spot forming unit (SFU)/10(6) peripheral blood mononuclear cells (PBMC)], diverse (multiple immunodominant epitopes) IFN-γ responses and antigen-specific perforin release (average 332 SFU/10(6) PBMCs), suggesting that phTERT breaks tolerance and induces potent cytotoxic responses in this human-relevant model. Moreover, in an HPV16-associated tumor model, vaccination of phTERT slows tumor growth and improves survival rate in both prophylactic and therapeutic studies. Finally, in vivo cytotoxicity assay confirmed that phTERT-induced CD8 T cells exhibited specific cytotoxic T lymphocyte (CTL) activity, capable of eliminating hTERT-pulsed target cells. These findings support that this synthetic electroporation-delivered DNA phTERT may have a role as a broad therapeutic cancer vaccine candidate.
Collapse
Affiliation(s)
- Jian Yan
- Inovio Pharmaceuticals, Inc., 1787 Sentry Parkway West, Building 18, Suite 400, Blue Bell, PA 19422
| | - Panyupa Pankhong
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Thomas H Shin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nyamekye Obeng-Adjei
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew P Morrow
- Inovio Pharmaceuticals, Inc., 1787 Sentry Parkway West, Building 18, Suite 400, Blue Bell, PA 19422
| | - Jewell N Walters
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Amir S Khan
- Inovio Pharmaceuticals, Inc., 1787 Sentry Parkway West, Building 18, Suite 400, Blue Bell, PA 19422
| | - Niranjan Y Sardesai
- Inovio Pharmaceuticals, Inc., 1787 Sentry Parkway West, Building 18, Suite 400, Blue Bell, PA 19422
| | - David B Weiner
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|