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Advances in the Histone Acetylation Modification in the Oral Squamous Cell Carcinoma. JOURNAL OF ONCOLOGY 2023. [DOI: 10.1155/2023/4616682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Oral squamous cell carcinoma (OSCC) is one of the common malignant tumors in the head and neck, characterized by high malignancy, rapid growth and metastasis, high invasive ability, and high mortality. In recent years, surgery combined with chemotherapy or radiotherapy remains the preferred clinical treatment for OSCC, despite considerable advances in diagnostic and therapeutic techniques. Hence, new targeted therapy is urgently needed. Histone modification affects the function of massive cells through histone acetyltransferase and histone deacetylase. Accompanied by the progress of some diseases, especially tumors, these proteins often show abnormal functions, and by reversing these abnormalities with drugs or gene therapy, the cancer phenotype can even be restored to normal. As a result, they are potential drug targets. This article reviewed the role of the histone dynamic process of acetylation modifications and their associated active modifying enzymes in the pathogenesis and progress of OSCC. Moreover, we explored the value of histone acetylation modification as a potential therapeutic target and the new progress of related drugs in clinical treatment.
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Chen X, Tang WJ, Shi JB, Liu MM, Liu XH. Therapeutic strategies for targeting telomerase in cancer. Med Res Rev 2019; 40:532-585. [PMID: 31361345 DOI: 10.1002/med.21626] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 07/12/2019] [Accepted: 07/16/2019] [Indexed: 12/13/2022]
Abstract
Telomere and telomerase play important roles in abnormal cell proliferation, metastasis, stem cell maintenance, and immortalization in various cancers. Therefore, designing of drugs targeting telomerase and telomere is of great significance. Over the past two decades, considerable knowledge regarding telomere and telomerase has been accumulated, which provides theoretical support for the design of therapeutic strategies such as telomere elongation. Therefore, the development of telomere-based therapies such as nucleoside analogs, non-nucleoside small molecules, antisense technology, ribozymes, and dominant negative human telomerase reverse transcriptase are being prioritized for eradicating a majority of tumors. While the benefits of telomere-based therapies are obvious, there is a need to address the limitations of various therapeutic strategies to improve the possibility of clinical applications. In this study, current knowledge of telomere and telomerase is discussed, and therapeutic strategies based on recent research are reviewed.
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Affiliation(s)
- Xing Chen
- School of Pharmacy, Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei, People's Republic of China
| | - Wen-Jian Tang
- School of Pharmacy, Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei, People's Republic of China
| | - Jing Bo Shi
- School of Pharmacy, Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei, People's Republic of China
| | - Ming Ming Liu
- School of Pharmacy, Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei, People's Republic of China
| | - Xin-Hua Liu
- School of Pharmacy, Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei, People's Republic of China
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Yang H, Jin X, Dan H, Chen Q. Histone modifications in oral squamous cell carcinoma and oral potentially malignant disorders. Oral Dis 2019; 26:719-732. [PMID: 31056829 DOI: 10.1111/odi.13115] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 04/17/2019] [Accepted: 04/29/2019] [Indexed: 02/05/2023]
Affiliation(s)
- Huamei Yang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Chinese Academy of Medical Sciences Research Unit of Oral Medicine of Carcinogenesis and Management West China Hospital of Stomatology, Sichuan University Chengdu China
| | - Xin Jin
- College of Stomatology Chongqing Medical University Chongqing China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Chongqing China
| | - Hongxia Dan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Chinese Academy of Medical Sciences Research Unit of Oral Medicine of Carcinogenesis and Management West China Hospital of Stomatology, Sichuan University Chengdu China
| | - Qianming Chen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Chinese Academy of Medical Sciences Research Unit of Oral Medicine of Carcinogenesis and Management West China Hospital of Stomatology, Sichuan University Chengdu China
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Martin SL, Kala R, Tollefsbol TO. Mechanisms for the Inhibition of Colon Cancer Cells by Sulforaphane through Epigenetic Modulation of MicroRNA-21 and Human Telomerase Reverse Transcriptase (hTERT) Down-regulation. Curr Cancer Drug Targets 2018; 18:97-106. [PMID: 28176652 PMCID: PMC5577390 DOI: 10.2174/1568009617666170206104032] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 03/15/2016] [Accepted: 09/30/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND Epigenetic modulations such as histone modifications are becoming increasingly valued for their ability to modify genes without altering the DNA sequence. Many bioactive compounds have been shown to alter genetic and epigenetic profiles in various cancers. Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables such as kale, cabbage and broccoli sprouts, is one of the most potent histone deacetylase inhibitors (HDACis) to date. Recently, it has been identified that HDACis may play a vital role in regulating microRNAs (miRs) and human telomerase reverse transcriptase (hTERT). OBJECTIVE The aim of our study was to identify if aberrant HDAC, hTERT and miR levels could be regulated through novel dietary-based approaches in colorectal cancer (CRC) cells. METHODS We evaluated the in vitro epigenetic effects of SFN on CRC cells by MTT assay, cellular density assay, real-time reverse transcriptase-polymerase chain reaction (RT-PCR), cell cycle analysis, western-blot assay, HDAC activity assay and teloTAGGG telomerase PCR Elisa assay. RESULTS We demonstrated the inhibitory effects of physiologically relevant concentrations of SFN in both HCT116 and RKO CRC cells, and showed for the first time that SFN treatment decreased cell density, significantly inhibited cell viability and induced apoptosis in CRC cells. We also found that practical doses of SFN significantly down-regulated oncogenic miR-21, HDAC and hTERT mRNA, protein and enzymatic levels in CRC cells. CONCLUSION Our studies suggest that the regulation of HDAC, hTERT and miR-21 is a promising approach for delaying and/or preventing CRC and may be accomplished via the consumption of SFN in cruciferous vegetables.
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Affiliation(s)
- Samantha L Martin
- Department of Biology, University of Alabama at Birmingham, 1300 University Boulevard, Birmingham, AL 35294, United States
| | - Rishabh Kala
- Department of Biology, University of Alabama at Birmingham, 1300 University Boulevard, Birmingham, AL 35294, United States
| | - Trygve O Tollefsbol
- Department of Biology, University of Alabama at Birmingham, 1300 University Boulevard, Birmingham, AL 35294, United States
- Comprehensive Center for Healthy Aging, University of Alabama Birmingham, 1530 3rd Avenue South, Birmingham, AL 35294, United States
- Comprehensive Cancer Center, University of Alabama Birmingham, 1802 6th Avenue South, Birmingham, AL 35294, United States
- Nutrition Obesity Research Center, University of Alabama Birmingham, 1675 University Boulevard, Birmingham, AL 35294, United States
- Comprehensive Diabetes Center, University of Alabama Birmingham, 1825 University Boulevard, Birmingham, AL 35294, United States
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5
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Kumar A, Nilednu P, Kumar A, Sharma NK. Epigenetic perturbation driving asleep telomerase reverse transcriptase: Possible therapeutic avenues in carcinoma. Tumour Biol 2017; 39:1010428317695951. [DOI: 10.1177/1010428317695951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In the last decade, implications of human telomerase reverse transcriptase (hTERT), a component of ribonucleoprotein telomerase in aging, senescence, and stem cell are highly evident. Besides, the activation of hTERT is also being documented several cancer types including carcinoma. The awakening of telomerase during carcinoma initiation and development is being seen with different perspectives including genetic and epigenetic tools and events. In view of several tumor progenitors genes (also referred as epigenetic mediators), telomerase is placed as key enzyme to achieve the carcinoma phenotype and sustain during the progression. It is true that swaying of telomerase in carcinoma could be facilitated with dedicated set of epigenetic modulators and modifiers players. These epigenetic alterations are heritable, potentially reversible, and seen as the epigenetic signature of carcinoma. Several papers converge to suggest that DNA methylation, histone modification, and small non-coding RNAs are the widely appreciated epigenetic changes towards hTERT modulation. In this review, we summarize the contribution of epigenetic factors in the telomerase activation and discuss potential avenues to achieve therapeutic intervention in carcinoma.
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Affiliation(s)
- Ajay Kumar
- Cancer and Translational Research Lab, Department of Biotechnology, Dr. D. Y. Patil Biotechnology & Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Pune, India
| | - Pritish Nilednu
- Cancer and Translational Research Lab, Department of Biotechnology, Dr. D. Y. Patil Biotechnology & Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Pune, India
| | - Azad Kumar
- Cancer and Translational Research Lab, Department of Biotechnology, Dr. D. Y. Patil Biotechnology & Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Pune, India
| | - Nilesh Kumar Sharma
- Cancer and Translational Research Lab, Department of Biotechnology, Dr. D. Y. Patil Biotechnology & Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Pune, India
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Boscolo-Rizzo P, Da Mosto MC, Rampazzo E, Giunco S, Del Mistro A, Menegaldo A, Baboci L, Mantovani M, Tirelli G, De Rossi A. Telomeres and telomerase in head and neck squamous cell carcinoma: from pathogenesis to clinical implications. Cancer Metastasis Rev 2017; 35:457-74. [PMID: 27501725 PMCID: PMC5035656 DOI: 10.1007/s10555-016-9633-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Strongly associated with tobacco use, heavy alcohol consumption, and with high-risk human papillomavirus (HPV) infection, head and neck squamous cell carcinoma (HNSCC) is a frequently lethal, heterogeneous disease whose pathogenesis is a multistep and multifactorial process involving genetic and epigenetic events. The majority of HNSCC patients present with locoregional advanced stage disease and are treated with combined modality strategies that can markedly impair quality of life and elicit unpredictable results. A large fraction of those who undergo locoregional treatment and achieve a complete response later develop locoregional recurrences or second field tumors. Biomarkers that are thus able to stratify risk and enable clinicians to tailor treatment plans and to personalize post-therapeutic surveillance strategies are highly desirable. To date, only HPV status is considered a reliable independent predictor of treatment response and survival in patients with HNSCC arising from the oropharyngeal site. Recent studies suggest that telomere attrition, which may be an early event in human carcinogenesis, and telomerase activation, which is detected in up to 90 % of malignancies, could be potential markers of cancer risk and disease outcome. This review examines the current state of knowledge on and discusses the implications linked to telomere dysfunction and telomerase activation in the development and clinical outcome of HNSCC.
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MESH Headings
- Animals
- Biomarkers, Tumor
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/mortality
- Carcinoma, Squamous Cell/pathology
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Gene Expression Regulation, Neoplastic
- Genetic Predisposition to Disease
- Genetic Variation
- Genomic Instability
- Head and Neck Neoplasms/genetics
- Head and Neck Neoplasms/metabolism
- Head and Neck Neoplasms/mortality
- Head and Neck Neoplasms/pathology
- Humans
- Leukocytes, Mononuclear/metabolism
- Leukocytes, Mononuclear/pathology
- Mice
- Prognosis
- Squamous Cell Carcinoma of Head and Neck
- Telomerase/metabolism
- Telomere/genetics
- Telomere Homeostasis
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Affiliation(s)
- Paolo Boscolo-Rizzo
- Section of Otolaryngology and Regional Centre for Head and Neck Cancer, Department of Neurosciences, University of Padova, Treviso, Italy
| | - Maria Cristina Da Mosto
- Section of Otolaryngology and Regional Centre for Head and Neck Cancer, Department of Neurosciences, University of Padova, Treviso, Italy
| | - Enrica Rampazzo
- Section of Oncology and Immunology, Department of Surgical Sciences, Oncology and Gastroenterology, University of Padova, via Gattamelata 64, 35128, Padova, Italy
| | - Silvia Giunco
- Section of Oncology and Immunology, Department of Surgical Sciences, Oncology and Gastroenterology, University of Padova, via Gattamelata 64, 35128, Padova, Italy
| | - Annarosa Del Mistro
- Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto-IRCCS, Padova, Italy
| | - Anna Menegaldo
- Section of Otolaryngology and Regional Centre for Head and Neck Cancer, Department of Neurosciences, University of Padova, Treviso, Italy
| | - Lorena Baboci
- Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto-IRCCS, Padova, Italy
| | - Monica Mantovani
- Section of Otolaryngology and Regional Centre for Head and Neck Cancer, Department of Neurosciences, University of Padova, Treviso, Italy
| | - Giancarlo Tirelli
- Department of Otorhinolaryngology and Head and Neck Surgery, University of Trieste, Trieste, Italy
| | - Anita De Rossi
- Section of Oncology and Immunology, Department of Surgical Sciences, Oncology and Gastroenterology, University of Padova, via Gattamelata 64, 35128, Padova, Italy.
- Immunology and Molecular Oncology Unit, Istituto Oncologico Veneto-IRCCS, Padova, Italy.
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Abstract
Oral squamous cell carcinoma (OSCC) is the most common type of oral neoplasm, accounting for over 90% of all oral malignancies and 38% of head and neck tumors. Worldwide, OSCC is the eighth most common human cancer, with more than 500,000 new cases being diagnosed every year with a fairly onerous prognosis, encouraging further research on factors that might modify disease outcome. Genetic and/or environmental risk factors associated with the development of oral cancer have been sufficiently understood (smoking, alcohol, betel, diet, living habits, etc.). Knowledge of the genetic basis in oral carcinogenesis is still a challenging task. To improve the diagnosis and prevention, a previously unknown type of chromatin modification, known as epigenetic, which is defined as heritable DNA changes that are not encoded in the sequence itself and which are reversible and increasingly appear to serve fundamental roles in cell differentiation and development are studied. Tumors shed their DNA into the blood and epigenetic changes that occur early during tumorigenesis, sometimes even in premalignant lesions, can provide valuable biomarkers. Key components involved in epigenetic regulation are DNA methylation, histone modifications and modifications in micro ribonucleic acids (miRNAs). Epigenetic modifications may contribute to aberrant epigenetic mechanisms seen in oral precancers and cancers. In the near future, epigenetic variations found in oral dysplastic cells can act as a molecular fingerprint for malignancies.
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Affiliation(s)
- K N Hema
- Department of Oral and Maxillofacial Pathology, V.S. Dental College and Hospital, Bengaluru, Karnataka, India
| | - T Smitha
- Department of Oral and Maxillofacial Pathology, V.S. Dental College and Hospital, Bengaluru, Karnataka, India
| | - H S Sheethal
- Department of Oral and Maxillofacial Pathology, V.S. Dental College and Hospital, Bengaluru, Karnataka, India
| | - S Angeline Mirnalini
- Department of Oral and Maxillofacial Pathology, V.S. Dental College and Hospital, Bengaluru, Karnataka, India
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8
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HDAC1 and HDAC2 integrate the expression of p53 mutants in pancreatic cancer. Oncogene 2016; 36:1804-1815. [PMID: 27721407 DOI: 10.1038/onc.2016.344] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 08/05/2016] [Accepted: 08/15/2016] [Indexed: 12/25/2022]
Abstract
Mutation of p53 is a frequent genetic lesion in pancreatic cancer being an unmet clinical challenge. Mutants of p53 have lost the tumour-suppressive functions of wild type p53. In addition, p53 mutants exert tumour-promoting functions, qualifying them as important therapeutic targets. Here, we show that the class I histone deacetylases HDAC1 and HDAC2 contribute to maintain the expression of p53 mutants in human and genetically defined murine pancreatic cancer cells. Our data reveal that the inhibition of these HDACs with small molecule HDAC inhibitors (HDACi), as well as the specific genetic elimination of HDAC1 and HDAC2, reduce the expression of mutant p53 mRNA and protein levels. We further show that HDAC1, HDAC2 and MYC directly bind to the TP53 gene and that MYC recruitment drops upon HDAC inhibitor treatment. Therefore, our results illustrate a previously unrecognized class I HDAC-dependent control of the TP53 gene and provide evidence for a contribution of MYC. A combined approach targeting HDAC1/HDAC2 and MYC may present a novel and molecularly defined strategy to target mutant p53 in pancreatic cancer.
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9
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Chen Y, Zhang Y. Functional and mechanistic analysis of telomerase: An antitumor drug target. Pharmacol Ther 2016; 163:24-47. [DOI: 10.1016/j.pharmthera.2016.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/29/2016] [Indexed: 01/26/2023]
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10
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Melicher D, Buzas EI, Falus A. Genetic and epigenetic trends in telomere research: a novel way in immunoepigenetics. Cell Mol Life Sci 2015; 72:4095-109. [PMID: 26190020 PMCID: PMC11113282 DOI: 10.1007/s00018-015-1991-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 06/25/2015] [Accepted: 07/10/2015] [Indexed: 01/09/2023]
Abstract
Telomeres are protective heterochromatic structures that cap the end of linear chromosomes and play a key role in preserving genomic stability. Telomere length represents a balance between processes that shorten telomeres during cell divisions with incomplete DNA replication and the ones that lengthen telomeres by the action of telomerase, an RNA-protein complex with reverse transcriptase activity which adds telomeric repeats to DNA molecule ends. Telomerase activity and telomere length have a crucial role in cellular ageing and in the pathobiology of several human diseases attracting intense research. The last few decades have witnessed remarkable advances in our understanding about telomeres, telomere-associated proteins, and the biogenesis and regulation of the telomerase holoenzyme complex, as well as about telomerase activation and the telomere-independent functions of telomerase. Emerging data have revealed that telomere length can be modified by genetic and epigenetic factors, sex hormones, reactive oxygen species and inflammatory reactions. It has become clear that, in order to find out more about the factors influencing the rate of telomere attrition in vivo, it is crucial to explore both genetic and epigenetic mechanisms. Since the telomere/telomerase assembly is under the control of multiple epigenetic influences, the unique design of twin studies could help disentangle genetic and environmental factors in the functioning of the telomere/telomerase system. It is surprising that the literature on twin studies investigating this topic is rather scarce. This review aims to provide an overview of some important immune response- and epigenetics-related aspects of the telomere/telomerase system demanding more research, while presenting the available twin data published in connection with telomere research so far. By emphasising what we know and what we still do not know in these areas, another purpose of this review is to urge more twin studies in telomere research.
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Affiliation(s)
- Dora Melicher
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Edit I Buzas
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Andras Falus
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary.
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11
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Human telomerase inhibitors from microbial source. World J Microbiol Biotechnol 2015; 31:1329-41. [DOI: 10.1007/s11274-015-1893-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 06/18/2015] [Indexed: 12/31/2022]
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12
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Jewett A, Man YG, Cacalano N, Kos J, Tseng HC. Natural killer cells as effectors of selection and differentiation of stem cells: role in resolution of inflammation. J Immunotoxicol 2014; 11:297-307. [PMID: 24575813 DOI: 10.3109/1547691x.2013.877104] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Evidence has previously been demonstrated for the role of NK cells in specific elimination of healthy stem cells (e.g. hMSC, hDPSC, hESC, hiPSC) as well as cancer stem cells, but not their differentiated counterparts. There is also a stage-wise susceptibility to NK cell-mediated cyto-toxicity in tumors, in which case the poorly-differentiated tumors are lysed much more than moderately-differentiated tumors. Well-differentiated tumors were lysed the least compared to either moderately- or poorly-differentiated tumors. It has also been reported that inhibition of differentiation or reversion of cells to a less-differentiated stage by blocking NF-κB or by gene deletion of COX2 significantly augmented NK cell cytotoxicity against both transformed and healthy cells. Additionally, the cytotoxic function of NK cells was severely inhibited against stem cells when they were cultured in the presence of monocytes. Therefore, it is proposed that CD16(+)CD56(dim)CD69(-) NK cells were important for the selection of stem cells, whereas the CD16(dim/-)CD56(dim/+)CD69(+) anergized NK cells were important for differentiation and eventual regeneration of the tissues and the resolution of inflammation, thus potentially serving as regulatory NK (NK(reg)) cells. The concept of 'split anergy' in NK cells and the generation of NK(reg) cells with regard to contributions to cell differentiation, tissue repair and regeneration and in tumor resistance are discussed in this review.
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Affiliation(s)
- Anahid Jewett
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, and Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California , Los Angeles, CA , USA
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13
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Sui X, Kong N, Wang Z, Pan H. Epigenetic regulation of the human telomerase reverse transciptase gene: A potential therapeutic target for the treatment of leukemia (Review). Oncol Lett 2013; 6:317-322. [PMID: 24137323 PMCID: PMC3789043 DOI: 10.3892/ol.2013.1367] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 05/17/2013] [Indexed: 12/21/2022] Open
Abstract
Telomerase activation is a critical step in human carcinogenesis through the maintenance of telomeres. Telomerase activity is primarily regulated by the human telomerase reverse transcriptase gene (hTERT), thus, an improved understanding of the transcriptional control of hTERT may provide potential therapeutic targets for the treatment of leukemia and other forms of cancer. Epigenetic modulation, a significant regulatory process in cell biology, has recently been shown to be involved in the regulation of the hTERT gene. Moreover, several epigenetic modifiers, including DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitors, are now in pre- and early clinical trials of leukemia as monotherapies or in combination with other drugs, and have achieved significant clinical success. In the present review, the epigenetic mechanisms associated with telomerase activity in leukemia, and the therapeutic potential of an antitelomerase strategy that combines epigenetic modifiers with telomerase hTR subunit small molecule inhibitors are discussed.
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Affiliation(s)
- Xinbing Sui
- Department of Medical Oncology, Sir Run Run Shaw Hospital, Zhejiang University, P.R. China
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14
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Abstract
Dysregulation of gene expression is a frequent occurrence in oral squamous cell carcinoma (OSCC). However, accumulating evidence suggests that in contrast to genetics, epigenetic modifications consisting of aberrant DNA methylation, histone modifications and altered expression of miRNAs induce OSCC tumorigenesis and perhaps play a more central role in the evolution and progression of this disease. The unifying theme among these three epigenetic mechanisms remains the same, which is aberrant regulation of gene expression. In this article, we provide a comprehensive review of the impact of epigenetics on oral tumorigenesis with a systematic report on aberrant DNA methylation, histone modifications and miRNA regulation in the pathogenesis of OSCC. We provide insights into recent studies on the prospect of biomarkers for early detection and indication of disease recurrence, and novel treatment modalities.
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Affiliation(s)
- Jacqueline A Gasche
- Division of Gastroenterology, Department of Internal Medicine, Charles A Sammons Cancer Center & Baylor Research Institute, Baylor University Medical Center, 3500 Gaston Avenue, Suite 250 Hoblitzelle, Dallas, TX 75246, USA
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15
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Yu M, Kong H, Zhao Y, Sun X, Zheng Z, Yang C, Zhu Y. Enhancement of adriamycin cytotoxicity by sodium butyrate involves hTERT downmodulation-mediated apoptosis in human uterine cancer cells. Mol Carcinog 2013; 53:505-13. [PMID: 23359532 DOI: 10.1002/mc.21998] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 12/04/2012] [Accepted: 12/07/2012] [Indexed: 12/30/2022]
Affiliation(s)
- Meng Yu
- Key Laboratory of Transgenetic Animal Research; Liaoning Province; Department of Laboratory Animal; China Medical University; Shenyang China
| | - Hong Kong
- Department of Clinical Laboratory; Shengjing Hospital of China Medical University; Shenyang China
| | - Yan Zhao
- Department of Gynecology; Shengjing Hospital of China Medical University; Shenyang China
| | - Xuefei Sun
- Department of Pharmaceutical Toxicology; School of Pharmaceutical Sciences; China Medical University; Shenyang China
| | - Zhihong Zheng
- Key Laboratory of Transgenetic Animal Research; Liaoning Province; Department of Laboratory Animal; China Medical University; Shenyang China
| | - Chunming Yang
- Department of Urology; First Affiliated Hospital of China Medical University; Shenyang China
| | - Yuyan Zhu
- Department of Urology; First Affiliated Hospital of China Medical University; Shenyang China
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16
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Jewett A, Man YG, Tseng HC. Dual functions of natural killer cells in selection and differentiation of stem cells; role in regulation of inflammation and regeneration of tissues. J Cancer 2012; 4:12-24. [PMID: 23386901 PMCID: PMC3564243 DOI: 10.7150/jca.5519] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Accepted: 11/25/2012] [Indexed: 02/06/2023] Open
Abstract
Accumulated evidence from our laboratory indicates that conditioned or anergized NK cells have the ability to induce resistance of healthy stem cells and transformed cancer stem cells through both secreted factors and direct cell-cell contact by inducing differentiation. Cytotoxic function of NK cells is suppressed in the tumor microenvironment by a number of distinct effectors and their secreted factors. Furthermore, decreased peripheral blood NK cell function has been documented in many cancer patients. We have previously shown that NK cells mediate significant cytotoxicity against primary oral squamous carcinoma stem cells (OSCSCs) as compared to their more differentiated oral squamous carcinoma cells (OSCCs). In addition, human embryonic stem cells (hESCs), human mesenchymal stem cells (hMSCs), human dental pulp stem cells (hDPSCs) and induced human pluripotent stem cells (hiPSCs) were all significantly more susceptible to NK cell mediated cytotoxicity than their differentiated counterparts or parental cells from which they were derived. We have also reported that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB or gene deletion of COX2 significantly augmented NK cell function. Furthermore, the induction of resistance of the stem cells to NK cell mediated cytotoxicity and their subsequent differentiation is amplified when either the stem cells or the NK cells were cultured in the presence of monocytes. Therefore, we propose that the two stages of NK cell maturation namely CD16+CD56dimCD69- NK cells are important for the lysis of stem cells or poorly differentiated cells whereas the CD16dim/-CD56dim/+CD69+NK cells are important for differentiation and eventual regeneration of the tissues and the resolution of inflammation, thus functionally serving as regulatory NK cells (NK(reg)). CD16 receptor on the NK cells were found to be the receptor with significant potential to induce NK cell anergy, however, our recent data indicated that NKp46 but not NKp30 or NKp44 were also able to induce significant anergy in NK cells, although the levels were less when compared to CD16 receptor triggering. The concept of split anergy in NK cells and generation of NK(reg) and its contribution to cell differentiation, tissue repair and regeneration and in tumor resistance will be discussed in this review.
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Affiliation(s)
- Anahid Jewett
- 1. The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, and Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California, Los Angeles, CA 90095
| | - Yan-Gao Man
- 2. The Diagnostic and Translational Research Center, Henry Jackson Foundation, Gaithersburg, MD
| | - Han-Ching Tseng
- 1. The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, and Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California, Los Angeles, CA 90095
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Mori K, Sato S, Kodama M, Habu M, Takahashi O, Nishihara T, Tominaga K, Takenaka S. Oral cancer diagnosis via a ferrocenylnaphthalene diimide-based electrochemical telomerase assay. Clin Chem 2012; 59:289-95. [PMID: 23136244 DOI: 10.1373/clinchem.2012.191569] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Telomerase is regarded as a good marker for cancer because it is unregulated in most tumor cells compared with normal cells. We evaluated telomerase activity in the lysate of tumor tissue and surrounding cells of oral cancer patients by an electrochemical technique, dubbed the electrochemical telomerase assay (ECTA). METHODS The assay used ferrocenylnaphthalene diimide (FND) as the probe. Electrochemical telomerase substrate (ETS) primer immobilized on the electrode was elongated by telomerase and FND bound to the product to give rise to a current. The data were standardized with the change in current before and after the elongation, respectively. RESULTS The change in current increased more than 30% in biopsy samples from most cancer patients, whereas the increase was 20% or lower in most healthy individuals. On the basis of this difference individual clinical samples were judged telomerase positive, ambiguous, or negative. The positive rates in the cancerous tissues and exfoliated cells (EOCs) of the patients were 85% and 90%, respectively, whereas the corresponding values were 50% and 10% by the telomerase repeat amplification protocol. Furthermore, the positive rate for the ECTA was 100% in early tumors smaller than 2 cm, and 95% and 82% of biopsy and exfoliated cells of healthy individuals were correctly judged as negative. Fifty-six unknown samples with EOCs tested were correctly judged to be cancerous or normal in 84% of cases. CONCLUSIONS The ECTA yielded high hit rates for cancerous and normal cells, especially in EOCs, results indicating that this minimally invasive test is suitable for oral cancer diagnosis.
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Affiliation(s)
- Kumiko Mori
- Department of Oral and Maxillofacial Surgery, Division of Maxillofacial Diagnostic and Surgical Science, Kyushu Dental College, Fukuoka, Japan
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Mascolo M, Siano M, Ilardi G, Russo D, Merolla F, De Rosa G, Staibano S. Epigenetic disregulation in oral cancer. Int J Mol Sci 2012; 13:2331-2353. [PMID: 22408457 PMCID: PMC3292026 DOI: 10.3390/ijms13022331] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 02/09/2012] [Accepted: 02/13/2012] [Indexed: 01/10/2023] Open
Abstract
Squamous cell carcinoma of the oral region (OSCC) is one of the most common and highly aggressive malignancies worldwide, despite the fact that significant results have been achieved during the last decades in its detection, prevention and treatment. Although many efforts have been made to define the molecular signatures that identify the clinical outcome of oral cancers, OSCC still lacks reliable prognostic molecular markers. Scientific evidence indicates that transition from normal epithelium to pre-malignancy, and finally to oral carcinoma, depends on the accumulation of genetic and epigenetic alterations in a multistep process. Unlike genetic alterations, epigenetic changes are heritable and potentially reversible. The most common examples of such changes are DNA methylation, histone modification, and small non-coding RNAs. Although several epigenetic changes have been currently linked to OSCC initiation and progression, they have been only partially characterized. Over the last decade, it has been demonstrated that especially aberrant DNA methylation plays a critical role in oral cancer. The major goal of the present paper is to review the recent literature about the epigenetic modifications contribution in early and later phases of OSCC malignant transformation; in particular we point out the current evidence of epigenetic marks as novel markers for early diagnosis and prognosis as well as potential therapeutic targets in oral cancer.
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Affiliation(s)
- Massimo Mascolo
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
| | - Maria Siano
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
| | - Gennaro Ilardi
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
| | - Daniela Russo
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
| | - Francesco Merolla
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
| | - Gaetano De Rosa
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
- Centro di Riferimento Oncologico di Basilicata (C.R.O.B.) Oncology Research Center of Basilicata, Rionero in Vulture, Potenza 85028, Italy
| | - Stefania Staibano
- Department of Biomorphological and Functional Sciences, Pathology Section, University of Naples “Federico II”, Naples 80131, Italy; E-Mails: (M.M.); (M.S.); (G.I.); (D.R.); (F.M.); (G.D.R.)
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Jewett A, Tseng HC. Potential rescue, survival and differentiation of cancer stem cells and primary non-transformed stem cells by monocyte-induced split anergy in natural killer cells. Cancer Immunol Immunother 2012; 61:265-274. [PMID: 22116348 PMCID: PMC11029795 DOI: 10.1007/s00262-011-1163-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Accepted: 11/11/2011] [Indexed: 01/14/2023]
Abstract
Cytotoxic function of NK cells is largely suppressed in the tumor microenvironment by a number of distinct effectors and their secreted factors. The aims of this review are to provide a rationale and a potential mechanism for immunosuppression in cancer and to demonstrate the significance of such immunosuppression in cellular differentiation and progression of cancer. We have recently shown that NK cells mediate significant cytotoxicity against primary oral squamous carcinoma stem cells (OSCSCs) as compared to their more differentiated oral squamous carcinoma cells. In addition, human embryonic stem cells, mesenchymal stem cells (hMSCs), dental pulp stem cells (hDPSCs) and induced pluripotent stem cells were all significantly more susceptible to NK-cell-mediated cytotoxicity than their differentiated counterparts or parental cells from which they were derived. We have also reported that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB significantly augmented NK-cell function. Total population of monocytes and those depleted of CD16+ subsets were able to substantially suppress NK-cell-mediated lysis of OSCSCs, hMSCs and hDPSCs. Overall, our results suggest that stem cells but not their differentiated counterparts are significant targets of the NK-cell cytotoxicity. The concept of split anergy in NK cells and its contribution to cell differentiation, tissue repair and regeneration and in tumor resistance and progression will be discussed in this review.
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Affiliation(s)
- Anahid Jewett
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, University of California, Los Angeles, CA, 90095-1668, USA.
- Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California, 10833 Le Conte Ave, Los Angeles, CA, 90095-1668, USA.
| | - Han-Ching Tseng
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, University of California, Los Angeles, CA, 90095-1668, USA
- Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California, 10833 Le Conte Ave, Los Angeles, CA, 90095-1668, USA
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García MPS, García-García A. Epigenome and DNA methylation in oral squamous cell carcinoma. Methods Mol Biol 2012; 863:207-19. [PMID: 22359295 DOI: 10.1007/978-1-61779-612-8_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Epigenetics studies and defines inherited changes in gene expression that are not encoded in the DNA sequence. The most studied epigenetic change in mammalian DNA is cytosine methylation in CpG dinucleotide areas. The other main group in epigenetic changes includes the posttranslational modifications of histones, mainly phosphorylation, deacetylation changes, and in the ubiquitinylation status. Oral squamous cell carcinoma is the most common malignancy of the oral cavity, and epigenetic changes are very common, as described in this chapter. Alterations in the DNA methylation status resulting from exposure to environmental stress agents have been documented even before birth. Although many epigenetic markers are potentially reversible, the mechanism still remains unclear and many epigenetic changes persist across cell lines and the life of the organism.
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Samartzis N, Imesch P, Dedes KJ, Samartzis EP, Fedier A, Fink D, Caduff R, Fehr MK. Expression pattern of class I histone deacetylases in vulvar intraepithelial neoplasia and vulvar cancer: a tissue microarray study. BMC Cancer 2011; 11:463. [PMID: 22029821 PMCID: PMC3229619 DOI: 10.1186/1471-2407-11-463] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 10/26/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Epigenetic regulation is an important mechanism leading to cancer initiation and promotion. Histone acetylation by histone deacetylases (HDACs) represents an important part of it. The development of HDAC inhibitors has identified the utility of HDACs as a therapeutic target. Little is known about the epigenetic regulation of vulvar intraepithelial neoplasia (VIN) and vulvar squamous cell cancer (VSCC). In this study, the expression of class I HDACs (HDAC 1, 2 and 3) was compared in a series of VIN and VSCC tissues. METHODS A tissue micro array (TMA) with specimens from 106 patients with high-grade VIN and 59 patients with vulvar cancer was constructed. The expression of HDACs 1, 2 and 3 were analyzed with immunohistochemistry (IHC). The nuclear expression pattern was evaluated in terms of intensity and percentage of stained nuclei and was compared between vulvar preinvasive lesions and vulvar cancer. RESULTS HDAC 2 expression was significantly higher in VIN than in VSCC (p < 0.001, Fisher's test). Also, 88.7% (n = 94/106) of VIN samples and only 54.5% (n = 31/57) of VSCC samples were scored at the maximum level. Conversely, HDAC 3 expression was significantly higher in VSCC (93%, 53/57) compared to VIN (73.6%, 78/106, p = 0.003), whereas only a small difference in the expression of HDAC 1 was found between these two entities of vulvar neoplasia. CONCLUSIONS These results suggest that epigenetic regulation plays a considerable role in the transformation of VIN to invasive vulvar neoplasia.
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Affiliation(s)
- Nicolas Samartzis
- Department of Gynecology, University Hospital Zurich, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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22
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Jewett A, Tseng HC. Tumor induced inactivation of natural killer cell cytotoxic function; implication in growth, expansion and differentiation of cancer stem cells. J Cancer 2011; 2:443-57. [PMID: 21850212 PMCID: PMC3157021 DOI: 10.7150/jca.2.443] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Accepted: 08/05/2011] [Indexed: 12/20/2022] Open
Abstract
Accumulated evidence indicates that cytotoxic function of immune effectors is largely suppressed in the tumor microenvironment by a number of distinct effectors and their secreted factors. The aims of this review are to provide a rationale and a potential mechanism for immunosuppression in cancer and to demonstrate the significance of such immunosuppression in cellular differentiation and progression of cancer. To that end, we have recently shown that NK cells mediate significant cytotoxicity against primary oral squamous carcinoma stem cells (OSCSCs) as compared to their more differentiated oral squamous carcinoma cells (OSCCs). In addition, human embryonic stem cells (hESCs), Mesenchymal Stem Cells (hMSCs), dental pulp stem cells (hDPSCs) and induced pluripotent stem cells (hiPSCs) were all significantly more susceptible to NK cell mediated cytotoxicity than their differentiated counterparts or parental cells from which they were derived. We have also reported that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB or targeted knock down of COX2 in primary monocytes in vivo significantly augmented NK cell function. Total population of monocytes and those depleted of CD16(+) subsets were able to substantially prevent NK cell mediated lysis of OSCSCs, MSCs and DPSCs. Taken together, our results suggest that stem cells are significant targets of the NK cell cytotoxicity. The concept of split anergy in NK cells and its contribution to tissue repair and regeneration and in tumor resistance and progression will be discussed in this review.
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Affiliation(s)
- Anahid Jewett
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, and Division of Oral Biology and Medicine, UCLA School of Dentistry, University of California, Los Angeles, CA 90095, USA
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Meeran SM, Patel SN, Tollefsbol TO. Sulforaphane causes epigenetic repression of hTERT expression in human breast cancer cell lines. PLoS One 2010; 5:e11457. [PMID: 20625516 PMCID: PMC2897894 DOI: 10.1371/journal.pone.0011457] [Citation(s) in RCA: 282] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 06/11/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables, is a common dietary component that has histone deacetylase inhibition activity and exciting potential in cancer prevention. The mechanisms by which SFN imparts its chemopreventive properties are of considerable interest and little is known of its preventive potential for breast cancer. PRINCIPAL FINDINGS We found that SFN significantly inhibits the viability and proliferation of breast cancer cells in vitro while it has negligible effects on normal breast cells. Inhibition of telomerase has received considerable attention because of its high expression in cancer cells and extremely low level of expression in normal cells. SFN treatment dose- and time-dependently inhibited human telomerase reverse transcriptase (hTERT), the catalytic regulatory subunit of telomerase, in both MCF-7 and MDA-MB-231 human breast cancer cells. DNA methyltransferases (DNMTs), especially DNMT1 and DNMT3a, were also decreased in SFN-treated breast cancer cells suggesting that SFN may repress hTERT by impacting epigenetic pathways. Down-regulation of DNMTs in response to SFN induced site-specific CpG demethylation occurring primarily in the first exon of the hTERT gene thereby facilitating CTCF binding associated with hTERT repression. Chromatin immunoprecipitation (ChIP) analysis of the hTERT promoter revealed that SFN increased the level of active chromatin markers acetyl-H3, acetyl-H3K9 and acetyl-H4, whereas the trimethyl-H3K9 and trimethyl-H3K27 inactive chromatin markers were decreased in a dose-dependent manner. SFN-induced hyperacetylation facilitated the binding of many hTERT repressor proteins such as MAD1 and CTCF to the hTERT regulatory region. Depletion of CTCF using siRNA reduced the SFN-induced down-regulation of hTERT mRNA transcription in these breast cancer cells. In addition, down-regulation of hTERT expression facilitated the induction of cellular apoptosis in human breast cancer cells. SIGNIFICANCE Collectively, our results provide novel insights into SFN-mediated epigenetic down-regulation of telomerase in breast cancer prevention and may open new avenues for approaches to SFN-mediated cancer prevention.
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Affiliation(s)
- Syed M. Meeran
- Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Shweta N. Patel
- Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Trygve O. Tollefsbol
- Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Center for Aging, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
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Iglesias-Linares A, Yañez-Vico R, González-Moles M. Potential role of HDAC inhibitors in cancer therapy: Insights into oral squamous cell carcinoma. Oral Oncol 2010; 46:323-9. [DOI: 10.1016/j.oraloncology.2010.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Revised: 01/15/2010] [Accepted: 01/15/2010] [Indexed: 01/13/2023]
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Abstract
Mounting effective anti-tumor immune responses against tumors by both the innate and adaptive immune effectors is important for the clearance of tumors. However, accumulated evidence indicates that immune responses that should otherwise suppress or eliminate transformed cells are themselves suppressed by the function of tumor cells in a variety of cancer patients, including those with oral cancers. Signaling abnormalities, spontaneous apoptosis, and reduced proliferation and function of circulating natural killer cells (NK), T-cells, dendritic cells (DC), and tumor-infiltrating lymphocytes (TILs) have been documented previously in oral cancer patients. Several mechanisms have been proposed for the functional deficiencies of tumor-associated immune cells in oral cancer patients. Both soluble factors and contact-mediated immunosuppression by the tumor cells have been implicated in the inhibition of immune cell function and the progression of tumors. More recently, elevated levels and function of key transcription factors in tumor cells, particularly NFkappaB and STAT3, have been shown to mediate immune suppression in the tumor microenvironment. This review will focus on these emerging mechanisms of immunosuppression in oral cancers.
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Affiliation(s)
- A Jewett
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Jonsson Comprehensive Cancer Center (JCCC), Department of Head and Neck Surgery, UCLA School of Dentistry and Medicine 90095-1688, USA.
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