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Chen Y, Dong H, Qu B, Ma X, Lu L. Protective effect of higher free thyroxine levels within the reference range on biliary tract cancer risk: a multivariable mendelian randomization and mediation analysis. Front Endocrinol (Lausanne) 2024; 15:1379607. [PMID: 38686204 PMCID: PMC11056546 DOI: 10.3389/fendo.2024.1379607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024] Open
Abstract
Background Hepatobiliary cancer (HBC), including hepatocellular carcinoma (HCC) and biliary tract cancer (BTC), is currently one of the malignant tumors that mainly cause human death. Many HBCs are diagnosed in the late stage, which increases the disease burden, indicating that effective prevention strategies and identification of risk factors are urgent. Many studies have reported the role of thyroid hormones on HBC. Our research aims to assess the causal effects and investigate the mediation effects between thyroid function and HBC. Methods Utilizing the Mendelian randomization (MR) approach, the study employs single nucleotide polymorphisms (SNPs) as instrumental variables (IVs) to explore causal links between thyroid function [free thyroxine (FT4), thyroid stimulating hormone (TSH), hyperthyroidism and hypothyroidism] and HBC. Data were sourced from the ThyroidOmic consortium and FinnGen consortium. The analysis included univariable and multivariable MR analysis, followed by mediation analysis. Results The study found a significant causal association between high FT4 levels and the reduced risk of BTC, but not HCC. However, TSH, hyperthyroidism and hypothyroidism had no causal associations with the risk of HBC. Notably, we also demonstrated that only higher FT4 levels with the reference range (FT4-RR) could reduce the risk of BTC because this protective effect no longer existed under the conditions of hyperthyroidism or hypothyroidism. Finally, we found that the protective effect of FT4-RR on BTC was mediated partially by decreasing the risk of metabolic syndrome (MetS) and reducing the waist circumference (WC). Conclusion The findings suggest that higher FT4-RR may have a protective effect against BTC, which is partially mediated by decreased risk of MetS and a reduction in WC. This study highlights the potential role of FT4 in the pathogenesis of BTC and underscores that MetS and WC may play mediation effects as two mediators in this process.
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Affiliation(s)
- Yuxian Chen
- College of Medicine, Qingdao University, Qingdao, China
| | - Hao Dong
- College of Medicine, Qingdao University, Qingdao, China
| | - Baozhen Qu
- Qingdao Cancer Prevention and Treatment Research Institute, Qingdao Central Hospital, University of Health and Rehabilitation Sciences (Qingdao Central Hospital), Qingdao, China
| | - Xuezhen Ma
- Department of Oncology, Qingdao Central Hospital, University of Health and Rehabilitation Sciences (Qingdao Central Hospital), Qingdao, China
| | - LinLin Lu
- Qingdao Cancer Prevention and Treatment Research Institute, Qingdao Central Hospital, University of Health and Rehabilitation Sciences (Qingdao Central Hospital), Qingdao, China
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2
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Xu L, Leng C, Chen L, Dong H, Chen Y, Chen X. Hypothyroidism is a predictive factor of superior antitumour efficacy of programmed death 1 inhibitors in hepatocellular carcinoma. Int J Cancer 2021; 150:472-481. [PMID: 34536292 DOI: 10.1002/ijc.33813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/13/2021] [Accepted: 09/09/2021] [Indexed: 12/19/2022]
Abstract
Programmed death 1 (PD-1) inhibitors are widely used for treatment of hepatocellular carcinoma (HCC). Hypothyroidism is commonly associated with this therapy, although the mechanism underlying this complication and effects on patient prognosis remain unclear. We retrospectively analysed the data of patients with HCC who received anti-PD-1 therapy at Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology between January 2018 and May 2020. Based on thyroid function evaluation, patients were categorised into hypothyroidism group and nonhypothyroidism group. Follow-up was completed on February 28, 2021. The primary endpoint of our study was progression free survival (PFS). The study included 74 patients, and the disease control rate was higher in hypothyroidism group (62.7%, 27/43) than in nonhypothyroidism group (36.4%, 11/31) (P = .020). The PFS was longer in hypothyroidism group (7.44 months) than in nonhypothyroidism group (5.68 months) (P = .006). Additionally, the PFS of patients with hypothyroidism before immunotherapy (6.27 months) was also longer than that in nonhypothyroidism group (5.68 months), although the difference was statistically nonsignificant (P = .527). Cox regression analysis showed that the hazard ratios of hypothyroidism, Child-Pugh grade B at initial admission and serum gamma-glutamyl transferase levels >71 U/L before immunotherapy were 0.404 (95% confidence interval [CI]: 0.207-0.791, P = .008), 2.753 (95%CI: 1.127-6.455, P = .026) and 2.469 (95%CI: 1.155-5.277, P = .020), respectively. Hypothyroidism was associated with prognosis in patients with HCC treated with PD-1 inhibitors, and prognosis was more favourable in patients with hypothyroidism than in those without hypothyroidism. Hypothyroidism and the Child-Pugh grade at initial admission were independently associated with patient prognosis.
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Affiliation(s)
- Lei Xu
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Chao Leng
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lin Chen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hanhua Dong
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yifa Chen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaoping Chen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Department of Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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3
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Lin YH, Lin KH, Yeh CT. Thyroid Hormone in Hepatocellular Carcinoma: Cancer Risk, Growth Regulation, and Anticancer Drug Resistance. Front Med (Lausanne) 2020; 7:174. [PMID: 32528965 PMCID: PMC7258858 DOI: 10.3389/fmed.2020.00174] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 04/15/2020] [Indexed: 12/16/2022] Open
Abstract
Thyroid hormone (TH) and its receptor (TR) are involved in differentiation, metabolic process, and growth regulation in hepatocellular carcinoma (HCC). The TH/TR complexes are ligand-dependent transcriptional factors, functioning through binding to thyroid hormone response elements (TREs) upstream of the target genes. To date, deciphering the biological effects of TH in cancer progression remains challenging. Several lines of evidence suggest a growth inhibitory effect of TH in liver cancer. Mutation and aberrant expression of TRs are highly correlated with several types of cancers including HCC. Several reports show that TH inhibits cell growth in liver cancer through regulation of cell-cycle-related genes and non-coding RNAs. A case–control study indicates that hypothyroidism is associated with an increased risk of HCC. Moreover, TH/TR suppresses hepatocarcinogenesis via selective autophagy. Conversely, other groups have indicated that TH promotes cancer cell proliferation. In vitro and in vivo experiments show that TH/TR enhances cancer cell migration and invasion, anticancer drug resistance, angiogenesis, and cancer stem cell self-renewal. Adding to the complexity of this issue, non-genomic effects of TH mediated by integrin receptor on cell surface can also modulate several biological functions. Accumulating evidence indicate that regulations by genomic and non-genomic effects of TH overlap. Taken together, these observations suggest that the functions of TH depend largely on cell context, and TH/TR plays a duel role in cancer progression. Therefore, understanding the maze of biological effects of TH has become a necessity when attempting to develop effective therapeutic and preventive strategies in liver cancer.
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Affiliation(s)
- Yang-Hsiang Lin
- Liver Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Kwang-Huei Lin
- Department of Biochemistry, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chau-Ting Yeh
- Liver Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan
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4
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Salomon MS, Malapati SH, O' Dwyer J, Silva CL, Williams CC, Barbeau MC, Yip D, Punzalan P, Nagle VL, Hinton SD, Roggero VR, Allison LA. Mislocalization of Cancer-associated Thyroid Hormone Receptor Mutants. NUCLEAR RECEPTOR RESEARCH 2020; 2020:https://web.archive.org/web/20210227193123/https://www.kenzpub.com/journals/nurr/inpress/2020/101453/. [PMID: 35280700 PMCID: PMC8909557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023] Open
Abstract
The thyroid hormone receptor (TR) is essential for the proper regulation of metabolism and development, as it regulates gene expression in response to thyroid hormone. Nuclear localization signals (NLSs) and nuclear export signals (NESs) allow for TR transport into and out of the nucleus, respectively. Previous research suggests that nuclear import, nuclear retention, and nuclear export of TR are associated with modulation of gene expression, the alteration of which can contribute to various diseases. Here, we examined the impact of cancer-associated mutations on TR localization patterns as a way of analyzing key structural components of TR and to further explore the correlation between TR trafficking, misfolding, and disease. Through mammalian cell transfection of expression plasmids for green fluorescent protein (GFP) and mCherry-tagged TRα1 and quantitative fluorescence microscopy, we examined particular groups of TRα1 mutations that were observed in patients with hepatocellular carcinoma, renal cell carcinoma, and thyroid cancer, and are associated with NLSs and NESs of TRα1. We also investigated structural alterations of the mutants by in silico modeling. Our results show striking shifts towards a more cytoplasmic localization for many of the mutants and an increased tendency to form cytosolic and nuclear aggregates.
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Affiliation(s)
- Michael S Salomon
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - S Harshini Malapati
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Jerry O' Dwyer
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Carolina Lopez Silva
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Cheyenne C Williams
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Michelle C Barbeau
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Delbert Yip
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Paige Punzalan
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Veronica L Nagle
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Shantá D Hinton
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Vincent R Roggero
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
| | - Lizabeth A Allison
- Department of Biology, William & Mary, 540 Landrum Drive, ISC 3035, Williamsburg, VA, 23185, USA
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5
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Manka P, Coombes JD, Boosman R, Gauthier K, Papa S, Syn WK. Thyroid hormone in the regulation of hepatocellular carcinoma and its microenvironment. Cancer Lett 2019; 419:175-186. [PMID: 29414304 DOI: 10.1016/j.canlet.2018.01.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/14/2018] [Accepted: 01/18/2018] [Indexed: 02/07/2023]
Abstract
Hepatocellular carcinoma (HCC) commonly arises from a liver damaged by extensive inflammation and fibrosis. Various factors including cytokines, morphogens, and growth factors are involved in the crosstalk between HCC cells and the stromal microenvironment. Increasing our understanding of how stromal components interact with HCC and the signaling pathways involved could help identify new therapeutic and/or chemopreventive targets. It has become increasingly clear that the cross-talk between tumor cells and host stroma plays a key role in modulating tumor growth. Emerging reports suggest a relationship between HCC and thyroid hormone signaling (dysfunction), raising the possibility that perturbed thyroid hormone (TH) regulation influences the cancer microenvironment and cancer phenotype. This review provides an overview of the role of thyroid hormone and its related pathways in HCC and, specifically, its role in regulating the tumor microenvironment.
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Affiliation(s)
- P Manka
- Department of Gastroenterology and Hepatology, University Hospital Essen, Essen, Germany; Division of Gastroenterology and Hepatology, Department of Medicine, Medical University of South Carolina, Charleston (SC), USA.
| | - J D Coombes
- Regeneration and Repair, Institute of Hepatology, Division of Transplantation Immunology and Mucosal Biology, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - R Boosman
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - K Gauthier
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, CNRS UMR 5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - S Papa
- Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, United Kingdom
| | - W K Syn
- Division of Gastroenterology and Hepatology, Department of Medicine, Medical University of South Carolina, Charleston (SC), USA; Section of Gastroenterology, Ralph H Johnson Veteran Affairs Medical Center, Charleston (SC), USA.
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6
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Gionfra F, De Vito P, Pallottini V, Lin HY, Davis PJ, Pedersen JZ, Incerpi S. The Role of Thyroid Hormones in Hepatocyte Proliferation and Liver Cancer. Front Endocrinol (Lausanne) 2019; 10:532. [PMID: 31543862 PMCID: PMC6730500 DOI: 10.3389/fendo.2019.00532] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/17/2019] [Indexed: 12/13/2022] Open
Abstract
Thyroid hormones T3 and T4 (thyroxine) control a wide variety of effects related to development, differentiation, growth and metabolism, through their interaction with nuclear receptors. But thyroid hormones also produce non-genomic effects that typically start at the plasma membrane and are mediated mainly by integrin αvβ3, although other receptors such as TRα and TRβ are also able to elicit non-genomic responses. In the liver, the effects of thyroid hormones appear to be particularly important. The liver is able to regenerate, but it is subject to pathologies that may lead to cancer, such as fibrosis, cirrhosis, and non-alcoholic fatty liver disease. In addition, cancer cells undergo a reprogramming of their metabolism, resulting in drastic changes such as aerobic glycolysis instead of oxidative phosphorylation. As a consequence, the pyruvate kinase isoform M2, the rate-limiting enzyme of glycolysis, is dysregulated, and this is considered an important factor in tumorigenesis. Redox equilibrium is also important, in fact cancer cells give rise to the production of more reactive oxygen species (ROS) than normal cells. This increase may favor the survival and propagation of cancer cells. We evaluate the possible mechanisms involving the plasma membrane receptor integrin αvβ3 that may lead to cancer progression. Studying diseases that affect the liver and their experimental models may help to unravel the cellular pathways mediated by integrin αvβ3 that can lead to liver cancer. Inhibitors of integrin αvβ3 might represent a future therapeutic tool against liver cancer. We also include information on the possible role of exosomes in liver cancer, as well as on recent strategies such as organoids and spheroids, which may provide a new tool for research, drug discovery, and personalized medicine.
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Affiliation(s)
- Fabio Gionfra
- Department of Sciences, University Roma Tre, Rome, Italy
| | - Paolo De Vito
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | | | - Hung-Yun Lin
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Taipei Cancer Center, Taipei Medical University, Taipei, Taiwan
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, United States
- Traditional Herbal Medicine Research Center of Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
- Department of Medicine, Albany Medical College, Albany, NY, United States
| | - Paul J. Davis
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, United States
- Department of Medicine, Albany Medical College, Albany, NY, United States
| | - Jens Z. Pedersen
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Sandra Incerpi
- Department of Sciences, University Roma Tre, Rome, Italy
- *Correspondence: Sandra Incerpi
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7
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Krashin E, Piekiełko-Witkowska A, Ellis M, Ashur-Fabian O. Thyroid Hormones and Cancer: A Comprehensive Review of Preclinical and Clinical Studies. Front Endocrinol (Lausanne) 2019; 10:59. [PMID: 30814976 PMCID: PMC6381772 DOI: 10.3389/fendo.2019.00059] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 01/22/2019] [Indexed: 01/06/2023] Open
Abstract
Thyroid hormones take major part in normal growth, development and metabolism. Over a century of research has supported a relationship between thyroid hormones and the pathophysiology of various cancer types. In vitro studies as well as research in animal models demonstrated an effect of the thyroid hormones T3 and T4 on cancer proliferation, apoptosis, invasiveness and angiogenesis. Thyroid hormones mediate their effects on the cancer cell through several non-genomic pathways including activation of the plasma membrane receptor integrin αvβ3. Furthermore, cancer development and progression are affected by dysregulation of local bioavailability of thyroid hormones. Case-control and population-based studies provide conflicting results regarding the association between thyroid hormones and cancer. However, a large body of evidence suggests that subclinical and clinical hyperthyroidism increase the risk of several solid malignancies while hypothyroidism may reduce aggressiveness or delay the onset of cancer. Additional support is provided from studies in which dysregulation of the thyroid hormone axis secondary to cancer treatment or thyroid hormone supplementation was shown to affect cancer outcomes. Recent preclinical and clinical studies in various cancer types have further shown promising outcomes following chemical reduction of thyroid hormones or inhibition or their binding to the integrin receptor. This review provides a comprehensive overview of the preclinical and clinical research conducted so far.
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Affiliation(s)
- Eilon Krashin
- Translational Hemato-Oncology Laboratory, Meir Medical Center, Kfar-Saba, Israel
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | - Martin Ellis
- Translational Hemato-Oncology Laboratory, Meir Medical Center, Kfar-Saba, Israel
- Meir Medical Center, Hematology Institute and Blood Bank, Kfar-Saba, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Osnat Ashur-Fabian
- Translational Hemato-Oncology Laboratory, Meir Medical Center, Kfar-Saba, Israel
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- *Correspondence: Osnat Ashur-Fabian
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8
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Cicatiello AG, Ambrosio R, Dentice M. Thyroid hormone promotes differentiation of colon cancer stem cells. Mol Cell Endocrinol 2017; 459:84-89. [PMID: 28342853 DOI: 10.1016/j.mce.2017.03.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 03/16/2017] [Accepted: 03/18/2017] [Indexed: 01/14/2023]
Abstract
Tumor formation and maintenance depend on a small fraction of cancer stem cells (CSCs) that can self-renew and generate a wide variety of differentiated cells. CSCs are resistant to chemotherapy and radiation, and can represent a reservoir of cancer cells that often cause relapse after treatment. Evidence suggests that CSCs also give rise to metastases. Thyroid hormone (TH) controls a variety of biological processes including the development and functioning of most adult tissues. Recent years has seen the emergence of an intimate link between TH and multiple steps of tumorigenesis. Thyroid hormone controls the balance between the proliferation and differentiation of CSCs, and may thus be a druggable anti-cancer agent. Here, we review current understanding of the effects of TH on colorectal CSCs, including the cross regulatory loops between TH and regulators of CSC stemness. Targeting TH in the tumor microenvironment may improve treatment strategies.
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Affiliation(s)
| | | | - Monica Dentice
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Italy; CEINGE-Biotecnologie Avanzate S.c.ar.l., Naples, Italy.
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9
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Jimenez R, Privalsky ML. A resistance to thyroid hormone syndrome mutant operates through the target gene repertoire of the wild-type thyroid hormone receptor. Mol Cell Endocrinol 2017; 447:87-97. [PMID: 28257829 DOI: 10.1016/j.mce.2017.02.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 02/26/2017] [Accepted: 02/27/2017] [Indexed: 10/20/2022]
Abstract
Thyroid hormone receptors (TRs) play crucial roles in vertebrates. Wild-type (WT) TRs function primarily as hormone-regulated transcription factors. A human endocrine disease, Resistance to Thyroid Hormone (RTH)-Syndrome, is caused by inheritance of mutant TRs impaired in the proper regulation of target gene expression. To better understand the molecular basis of RTH we compared the target genes regulated by an RTH-TRβ1 mutant (R429Q) to those regulated by WT-TRβ1. With only a few potential exceptions, the vast majority of genes we were able to identify as regulated by the WT-TRβ1, positively or negatively, were also regulated by the RTH-TRβ1 mutant. We conclude that the actions of R429Q-TRβ1 in RTH-Syndrome most likely reflect the reduced hormone affinity observed for this mutant rather than an alteration in target gene repertoire. Our results highlight the importance of target gene specificity in defining the disease phenotype and improve our understanding of how clinical treatments impact RTH-Syndrome.
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Affiliation(s)
- Robyn Jimenez
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA
| | - Martin L Privalsky
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA.
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10
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Chi HC, Chen SL, Tsai CY, Chuang WY, Huang YH, Tsai MM, Wu SM, Sun CP, Yeh CT, Lin KH. Thyroid hormone suppresses hepatocarcinogenesis via DAPK2 and SQSTM1-dependent selective autophagy. Autophagy 2016; 12:2271-2285. [PMID: 27653365 DOI: 10.1080/15548627.2016.1230583] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Recent studies have demonstrated a critical association between disruption of cellular thyroid hormone (TH) signaling and the incidence of hepatocellular carcinoma (HCC), but the underlying mechanisms remain largely elusive. Here, we showed that disruption of TH production results in a marked increase in progression of diethylnitrosamine (DEN)-induced HCC in a murine model, and conversely, TH administration suppresses the carcinogenic process via activation of autophagy. Inhibition of autophagy via treatment with chloroquine (CQ) or knockdown of ATG7 (autophagy-related 7) via adeno-associated virus (AAV) vectors, suppressed the protective effects of TH against DEN-induced hepatic damage and development of HCC. The involvement of autophagy in TH-mediated protection was further supported by data showing transcriptional activation of DAPK2 (death-associated protein kinase 2; a serine/threonine protein kinase), which enhanced the phosphorylation of SQSTM1/p62 (sequestosome 1) to promote selective autophagic clearance of protein aggregates. Ectopic expression of DAPK2 further attenuated DEN-induced hepatoxicity and DNA damage though enhanced autophagy, whereas, knockdown of DAPK2 displayed the opposite effect. The pathological significance of the TH-mediated hepatoprotective effect by DAPK2 was confirmed by the concomitant decrease in the expression of THRs and DAPK2 in matched HCC tumor tissues. Taken together, these findings indicate that TH promotes selective autophagy via induction of DAPK2-SQSTM1 cascade, which in turn protects hepatocytes from DEN-induced hepatotoxicity or carcinogenesis.
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Affiliation(s)
- Hsiang-Cheng Chi
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan
| | - Shen-Liang Chen
- b Department of Life Sciences , National Central University , Jhongli , Taiwan
| | - Chung-Ying Tsai
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan
| | - Wen-Yu Chuang
- c Department of Pathology , Chang Gung Memorial Hospital and Chang Gung University College of Medicine , Taoyuan , Taiwan
| | - Ya-Hui Huang
- d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
| | - Ming-Ming Tsai
- e Department of Nursing , Chang-Gung University of Science and Technology , Taoyuan , Taiwan.,f Department of General Surgery , Chang Gung Memorial Hospital at Chiayi , Taiwan
| | - Sheng-Ming Wu
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan.,g Division of Pulmonary Medicine, Department of Internal Medicine , Shuang Ho Hospital, Taipei Medical University
| | - Cheng-Pu Sun
- h Institute of Biomedical Sciences, Academia Sinica , Taipei , Taiwan
| | - Chau-Ting Yeh
- d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
| | - Kwang-Huei Lin
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan.,d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
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11
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Chi HC, Chen SL, Cheng YH, Lin TK, Tsai CY, Tsai MM, Lin YH, Huang YH, Lin KH. Chemotherapy resistance and metastasis-promoting effects of thyroid hormone in hepatocarcinoma cells are mediated by suppression of FoxO1 and Bim pathway. Cell Death Dis 2016; 7:e2324. [PMID: 27490929 PMCID: PMC5108316 DOI: 10.1038/cddis.2016.227] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 06/21/2016] [Accepted: 06/28/2016] [Indexed: 01/08/2023]
Abstract
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, and systemic chemotherapy is the major treatment strategy for late-stage HCC patients. Poor prognosis following chemotherapy is the general outcome owing to recurrent resistance. Recent studies have suggested that in addition to cytotoxic effects on tumor cells, chemotherapy can induce an alternative cascade that supports tumor growth and metastasis. In the present investigation, we showed that thyroid hormone (TH), a potent hormone-mediating cellular differentiation and metabolism, acts as an antiapoptosis factor upon challenge of thyroid hormone receptor (TR)-expressing HCC cells with cancer therapy drugs, including cisplatin, doxorubicin and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). TH/TR signaling promoted chemotherapy resistance through negatively regulating the pro-apoptotic protein, Bim, resulting in doxorubicin-induced metastasis of chemotherapy-resistant HCC cells. Ectopic expression of Bim in hepatoma cells challenged with chemotherapeutic drugs abolished TH/TR-triggered apoptosis resistance and metastasis. Furthermore, Bim expression was directly transactivated by Forkhead box protein O1 (FoxO1), which was negatively regulated by TH/TR. TH/TR suppressed FoxO1 activity through both transcriptional downregulation and nuclear exclusion of FoxO1 triggered by Akt-mediated phosphorylation. Ectopic expression of the constitutively active FoxO1 mutant, FoxO1-AAA, but not FoxO1-wt, diminished the suppressive effect of TH/TR on Bim. Our findings collectively suggest that expression of Bim is mediated by FoxO1 and indirectly downregulated by TH/TR, leading to chemotherapy resistance and doxorubicin-promoted metastasis of hepatoma cells.
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Affiliation(s)
- Hsiang-Cheng Chi
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
| | - Shen-Liang Chen
- Department of Life Sciences, National Central University, Taoyuan 333, Taiwan, Republic of China
| | - Yi-Hung Cheng
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
| | - Tzu-Kang Lin
- Division of Neurosurgery, Chang Gung Memorial Hospital Linkou and Chang Gung University, Taoyuan 333, Taiwan, Republic of China
| | - Chung-Ying Tsai
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
| | - Ming-Ming Tsai
- Department of Nursing, Chang-Gung University of Science and Technology, Taoyuan 333, Taiwan.,Department of General Surgery, Chang Gung Memorial Hospital Chiayi 613, Taiwan
| | - Yang-Hsiang Lin
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
| | - Ya-Hui Huang
- Liver Research Center, Department of Hepato-Gastroenterology, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan
| | - Kwang-Huei Lin
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan.,Liver Research Center, Department of Hepato-Gastroenterology, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan
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12
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Hepatocellular carcinoma: thyroid hormone promotes tumorigenicity through inducing cancer stem-like cell self-renewal. Sci Rep 2016; 6:25183. [PMID: 27174710 PMCID: PMC4865859 DOI: 10.1038/srep25183] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 04/04/2016] [Indexed: 12/12/2022] Open
Abstract
Cancer stem-like cells (CSCs) play a key role in maintaining the aggressiveness of hepatocellular carcinoma (HCC), but the cell-biological regulation of CSCs is unclear. In the study, we report that thyroid hormone (TH) promotes cell self-renewal in HCC cells. TH also increases the percentage of CD90 + HCC cells and promotes drug resistance of HCC cells. By analyzing primary human HCC samples, we found that TRα transcript level is significantly elevated in primary liver cancer and portal vein metastatic tumor, compared to that of adjacent normal liver tissue. Knocking down TRα not only inhibits HCC self-renewal in vitro but also suppresses HCC tumor growth in vivo. Interestingly, treatment of TH leads to activation of NF-κB, which is required for the function of TH on inducing HCC cell self-renewal. We also found TRα and p65 cooperatively drive the expression of BMI1 by co-binding to the promoter region of BMI1 gene. In summary, our study uncovers a novel function of TH signaling in regulating the CSCs of HCC, and these findings might be useful for developing novel therapies by targeting TH function in HCC cells.
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13
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Martínez-Iglesias O, Alonso-Merino E, Aranda A. Tumor suppressive actions of the nuclear receptor corepressor 1. Pharmacol Res 2016; 108:75-79. [PMID: 27149915 DOI: 10.1016/j.phrs.2016.04.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 02/09/2023]
Abstract
Nuclear Receptor Corepressor 1 (NCoR) is an important transcriptional regulator that interacts with nuclear receptors and other transcription factors. Recent results have shown the presence of inactivating mutations or deletions of the NCoR gene in human tumors. NCoR has a strong tumor suppressor activity, inhibiting invasion, metastasis formation and tumor growth in xenograft mouse models. These changes are associated to transcriptional inhibition of genes linked to bad prognosis and increased metastasis in cancer patients. NCoR loss causes a long-term repression of NCoR gene transcription, suggesting that NCoR deficiency in the cancer cell could be propagated playing a role in tumor progression in the absence of NCoR gene mutations. The thyroid hormone receptor TRβ increases NCoR expression and this induction is essential in mediating the anti-metastatic and tumor suppressive actions of the receptor. Since metastasis is the main cause of cancer-related deaths, these results define NCoR as a potential target for cancer therapy.
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Affiliation(s)
- Olaia Martínez-Iglesias
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Spain
| | - Elvira Alonso-Merino
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Spain
| | - Ana Aranda
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Spain.
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14
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Autoregulatory loop of nuclear corepressor 1 expression controls invasion, tumor growth, and metastasis. Proc Natl Acad Sci U S A 2016; 113:E328-37. [PMID: 26729869 DOI: 10.1073/pnas.1520469113] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nuclear corepressor 1 (NCoR) associates with nuclear receptors and other transcription factors leading to transcriptional repression. We show here that NCoR depletion enhances cancer cell invasion and increases tumor growth and metastatic potential in nude mice. These changes are related to repressed transcription of genes associated with increased metastasis and poor prognosis in patients. Strikingly, transient NCoR silencing leads to heterochromatinization and stable silencing of the NCoR gene, suggesting that NCoR loss can be propagated, contributing to tumor progression even in the absence of NCoR gene mutations. Down-regulation of the thyroid hormone receptor β1 (TRβ) appears to be associated with cancer onset and progression. We found that expression of TRβ increases NCoR levels and that this induction is essential in mediating inhibition of tumor growth and metastasis by this receptor. Moreover, NCoR is down-regulated in human hepatocarcinomas and in the more aggressive breast cancer tumors, and its expression correlates positively with that of TRβ. These data provide a molecular basis for the anticancer actions of this corepressor and identify NCoR as a potential molecular target for development of novel cancer therapies.
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15
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Ruiz-Llorente L, Martínez-Iglesias O, García-Silva S, Tenbaum S, Regadera J, Aranda A. The thyroid hormone receptors as tumor suppressors. Horm Mol Biol Clin Investig 2015; 5:79-89. [PMID: 25961243 DOI: 10.1515/hmbci.2010.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Accepted: 09/08/2010] [Indexed: 12/18/2022]
Abstract
In addition to the well-known role of the thyroid hormone receptors (TRs) in growth, development and metabolism, there is increasing evidence that they have profound effects on cell proliferation and malignant transformation. TRs repress transcriptional induction of cyclin D1 by the ras oncogene and block transformation and tumor formation by Ras-transformed fibroblasts in nude mice. Mutant receptors that do not bind coactivators are able to display these actions, whereas receptors defective in corepressors binding are unable to antagonize the responses to the ras oncogene. Furthermore, expression of TRβ1 in hepatocarcinoma and breast cancer cells abolishes anchorage-independent growth and migration, blocks responses to growth factors and represses expression of prometastatic genes, reducing tumor growth and strongly inhibiting invasiveness, extravasation and metastasis formation in euthyroid mice. By contrast, when cells are inoculated into hypothyroid host, tumor growth is retarded, but tumors are more invasive and metastatic growth is enhanced. Increased aggressiveness and tumor growth retardation was also observed with parental cells that do not express TRs, showing that changes secondary to hypothyroidism can modulate tumor progression and metastatic growth independently of the presence of TRs on the tumor cells. Finally, increased malignancy of skin tumors is found in mice lacking TRs, further demonstrating the role of these receptors as inhibitors of tumor progression and suggesting that they represent a potential therapeutic target in cancer.
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16
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Medici M, Visser WE, Visser TJ, Peeters RP. Genetic determination of the hypothalamic-pituitary-thyroid axis: where do we stand? Endocr Rev 2015; 36:214-44. [PMID: 25751422 DOI: 10.1210/er.2014-1081] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
For a long time it has been known that both hypo- and hyperthyroidism are associated with an increased risk of morbidity and mortality. In recent years, it has also become clear that minor variations in thyroid function, including subclinical dysfunction and variation in thyroid function within the reference range, can have important effects on clinical endpoints, such as bone mineral density, depression, metabolic syndrome, and cardiovascular mortality. Serum thyroid parameters show substantial interindividual variability, whereas the intraindividual variability lies within a narrow range. This suggests that every individual has a unique hypothalamus-pituitary-thyroid axis setpoint that is mainly determined by genetic factors, and this heritability has been estimated to be 40-60%. Various mutations in thyroid hormone pathway genes have been identified in persons with thyroid dysfunction or altered thyroid function tests. Because these causes are rare, many candidate gene and linkage studies have been performed over the years to identify more common variants (polymorphisms) associated with thyroid (dys)function, but only a limited number of consistent associations have been found. However, in the past 5 years, advances in genetic research have led to the identification of a large number of new candidate genes. In this review, we provide an overview of the current knowledge about the polygenic basis of thyroid (dys)function. This includes new candidate genes identified by genome-wide approaches, what insights these genes provide into the genetic basis of thyroid (dys)function, and which new techniques will help to further decipher the genetic basis of thyroid (dys)function in the near future.
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Affiliation(s)
- Marco Medici
- Rotterdam Thyroid Center, Department of Internal Medicine, Erasmus Medical Center, 3015 GE Rotterdam, The Netherlands
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17
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Ruiz-Llorente L, Ardila-González S, Fanjul LF, Martínez-Iglesias O, Aranda A. microRNAs 424 and 503 are mediators of the anti-proliferative and anti-invasive action of the thyroid hormone receptor beta. Oncotarget 2015; 5:2918-33. [PMID: 24796297 PMCID: PMC4102780 DOI: 10.18632/oncotarget.1577] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The thyroid hormone receptors (TRs) mediate tumor suppressive effects in hepatocarcinoma and breast cancer cells. Here we show that incubation of hepatocarcinoma SK-hep1 cells expressing TRb with the thyroid hormone T3 induces transcription of the polycistronic message coding for microRNAs 424 and 503. TRb binds to the promoter region of these miRNAs and T3 induces an exchange of corepressors and coactivators inducing histone acetylation and transcriptional stimulation. We have validated cell cycle components as targets of these miRNAs. Overexpression of miR-424 mimicked the repressive effect of T3 on cell proliferation, growth in suspension, migration and invasion. Knockdown of miR-424 or miR-503 reduced the inhibitory effect of the hormone. T3 increased miR-424 and miR-503 in breast cancer cells expressing TRb, and this induction is also involved in the anti-invasive effects of the hormone. Furthermore, miR-424 or miR-503 depletion enhanced extravasation to the lungs of hepatocarcinoma cells injected in the tail vein of mice. The levels of these miRNAs were reduced in xenograft tumors formed in hypothyroid nude mice that are more invasive. Therefore, miR-424 or miR-503 mediate anti-proliferative and anti-invasive actions of TRb both in cultured cells and in vivo.
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Affiliation(s)
- Lidia Ruiz-Llorente
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Arturo Duperier 4, 28029 Madrid, Spain
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18
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Frau C, Loi R, Petrelli A, Perra A, Menegon S, Kowalik MA, Pinna S, Leoni VP, Fornari F, Gramantieri L, Ledda-Columbano GM, Giordano S, Columbano A. Local hypothyroidism favors the progression of preneoplastic lesions to hepatocellular carcinoma in rats. Hepatology 2015; 61:249-59. [PMID: 25156012 DOI: 10.1002/hep.27399] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 08/20/2014] [Indexed: 02/06/2023]
Abstract
UNLABELLED Thyroid hormone receptors (TRs) are ligand-dependent transcription factors that mediate most of the effects elicited by the thyroid hormone, 3,5,3'-L-triiodothyronine (T3). TRs have been implicated in tumorigenesis, although it is unclear whether they act as oncogenes or tumor suppressors, and at which stage of tumorigenesis their dysregulation occurs. Using the resistant-hepatocyte rat model (R-H model), we found down-regulation of TRβ1 and TRα1 and their target genes in early preneoplastic lesions and hepatocellular carcinoma (HCCs), suggesting that a hypothyroid status favors the onset and progression of preneoplastic lesions to HCC. Notably, TRβ1 and, to a lesser extent, TRα1 down-regulation was observed only in preneoplastic lesions positive for the progenitor cell marker, cytokeratin-19 (Krt-19) and characterized by a higher proliferative activity, compared to the Krt-19 negative ones. TRβ1 down-regulation was observed also in the vast majority of the analyzed human HCCs, compared to the matched peritumorous liver or to normal liver. Hyperthyroidism induced by T3 treatment caused up-regulation of TRβ1 and of its target genes in Krt-19(+) preneoplastic rat lesions and was associated with nodule regression. In HCC, TRβ1 down-regulation was not the result of hypermethylation of its promoter, but was associated with an increased expression of TRβ1-targeting microRNAs ([miR]-27a, -181a, and -204). An inverse correlation between TRβ1 and miR-181a was also found in human cirrhotic peritumoral tissue, compared to normal liver. CONCLUSION Down-regulation of TRs, especially TRβ1, is an early and relevant event in liver cancer development and is species and etiology independent. The results also suggest that a hypothyroid status of preneoplastic lesions may contribute to their progression to HCC and that the reversion of this condition may represent a possible therapeutic goal to interfere with the development of this tumor.
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Affiliation(s)
- Carla Frau
- Department of Biomedical Sciences, Unit of Oncology and Molecular Pathology, University of Cagliari, Cagliari, Italy
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19
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The functional significance of common polymorphisms in zinc finger transcription factors. G3-GENES GENOMES GENETICS 2014; 4:1647-55. [PMID: 24970883 PMCID: PMC4169156 DOI: 10.1534/g3.114.012195] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Variants that alter the DNA-binding specificity of transcription factors could affect the specificity for and expression of potentially many target genes, as has been observed in several tumor-derived mutations. Here we examined if such trans expression quantitative trait loci (trans-eQTLs) could similarly result from common genetic variants. We chose to focus on the Cys2-His2 class of zinc finger transcription factors because they are the most abundant superfamily of transcription factors in human and have well-characterized DNA binding interactions. We identified 430 SNPs that cause missense substitutions in the DNA-contacting residues. Fewer common missense SNPs were found at DNA-contacting residues compared with non-DNA-contacting residues (P = 0.00006), consistent with possible functional selection against SNPs at DNA-contacting positions. Functional predictions based on zinc finger transcription factor (ZNF) DNA binding preferences also suggested that many common substitutions could potentially alter binding specificity. However, Hardy-Weinberg Equilibrium analysis and examination of seven orthologs within the primate lineage failed to find evidence of trans-eQTLs associated with the DNA-contacting positions or evidence of a different selection pressure on a contemporary and evolutionary timescales. The overall conclusion was that common SNPs that alter the DNA-contacting residues of these factors are unlikely to produce strong trans-eQTLs, consistent with the observations by others that trans-eQTLs in humans tend to be few and weak. Some rare SNPs might alter specificity and remained rare due to purifying selection. The study also underscores the need for large-scale eQTLs mapping efforts that might provide experimental evidence for SNPs that alter the choice of transcription factor binding sites.
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20
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Abstract
Thyroid hormone receptors (TR) are prototypes of nuclear transcription factors that regulate the expression of target genes. These receptors play an important role in many physiological processes. Moreover, a dysfunction of these proteins is often implicated in several human diseases and malignancies. Here we report genetic variations and alterations of the TRs that have been described in the literature as well as their potential role in the development of some human diseases including cancers. The functional effects of some mutations and polymorphisms in TRs on disease susceptibility, especially on cancer risk, are now established. Therefore, further investigations are needed in order to use these receptors as therapeutic targets or as biological markers to decide on appropriate forms of treatment.
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Affiliation(s)
- Maha Rebaï
- Molecular and Cellular Diagnosis Processes, Centre of Biotechnology of Sfax, University of Sfax, Route Sidi Mansour, PO Box 1177, 3018 Sfax, Tunisia
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21
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Chi HC, Liao CH, Huang YH, Wu SM, Tsai CY, Liao CJ, Tseng YH, Lin YH, Chen CY, Chung IH, Wu TI, Chen WJ, Lin KH. Thyroid hormone receptor inhibits hepatoma cell migration through transcriptional activation of Dickkopf 4. Biochem Biophys Res Commun 2013; 439:60-5. [PMID: 23958302 DOI: 10.1016/j.bbrc.2013.08.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 08/08/2013] [Indexed: 11/30/2022]
Abstract
Triiodothyronine (T3) is a potent form of thyroid hormone mediates several physiological processes including cellular growth, development, and differentiation via binding to the nuclear thyroid hormone receptor (TR). Recent studies have demonstrated critical roles of T3/TR in tumor progression. Moreover, long-term hypothyroidism appears to be associated with the incidence of human hepatocellular carcinoma (HCC), independent of other major HCC risk factors. Dickkopf (DKK) 4, a secreted protein that antagonizes the canonical Wnt signaling pathway, is induced by T3 at both mRNA and protein levels in HCC cell lines. However, the mechanism underlying T3-mediated regulation of DKK4 remains unknown. In the present study, the 5' promoter region of DKK4 was serially deleted, and the reporter assay performed to localize the T3 response element (TRE). Consequently, we identified an atypical direct repeat TRE between nucleotides -1645 and -1629 conferring T3 responsiveness to the DKK4 gene. This region was further validated using chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). Stable DKK4 overexpression in SK-Hep-1 cells suppressed cell invasion and metastatic potential, both in vivo andin vitro, via reduction of matrix metalloproteinase-2 (MMP-2) expression. Our findings collectively suggest that DKK4 upregulated by T3/TR antagonizes the Wnt signal pathway to suppress tumor cell progression, thus providing new insights into the molecular mechanism underlying thyroid hormone activity in HCC.
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Affiliation(s)
- Hsiang-Cheng Chi
- Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC
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22
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The role of thyroid hormone signaling in the prevention of digestive system cancers. Int J Mol Sci 2013; 14:16240-57. [PMID: 23924944 PMCID: PMC3759909 DOI: 10.3390/ijms140816240] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 07/25/2013] [Accepted: 07/30/2013] [Indexed: 11/17/2022] Open
Abstract
Thyroid hormones play a critical role in the growth and development of the alimentary tract in vertebrates. Their effects are mediated by nuclear receptors as well as the cell surface receptor integrin αVβ3. Systemic thyroid hormone levels are controlled via activation and deactivation by iodothyronine deiodinases in the liver and other tissues. Given that thyroid hormone signaling has been characterized as a major effector of digestive system growth and homeostasis, numerous investigations have examined its role in the occurrence and progression of cancers in various tissues of this organ system. The present review summarizes current findings regarding the effects of thyroid hormone signaling on cancers of the esophagus, stomach, liver, pancreas, and colon. Particular attention is given to the roles of different thyroid hormone receptor isoforms, the novel integrin αVβ3 receptor, and thyroid hormone-related nutrients as possible protective agents and therapeutic targets. Future investigations geared towards a better understanding of thyroid hormone signaling in digestive system cancers may provide preventive or therapeutic strategies to diminish risk, improve outcome and avert recurrence in afflicted individuals.
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23
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Molecular functions of thyroid hormones and their clinical significance in liver-related diseases. BIOMED RESEARCH INTERNATIONAL 2013; 2013:601361. [PMID: 23878812 PMCID: PMC3708403 DOI: 10.1155/2013/601361] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 05/14/2013] [Accepted: 05/28/2013] [Indexed: 02/06/2023]
Abstract
Thyroid hormones (THs) are potent mediators of several physiological processes, including embryonic development, cellular differentiation, metabolism, and cell growth. Triiodothyronine (T3) is the most biologically active TH form. Thyroid hormone receptors (TRs) belong to the nuclear receptor superfamily and mediate the biological functions of T3 via transcriptional regulation. TRs generally form heterodimers with the retinoid X receptor (RXR) and regulate target genes upon T3 stimulation. Research over the past few decades has revealed that disruption of cellular TH signaling triggers chronic liver diseases, including alcoholic or nonalcoholic fatty liver disease and hepatocellular carcinoma (HCC). Animal model experiments and epidemiologic studies to date imply close associations between high TH levels and prevention of liver disease. Moreover, several investigations spanning four decades have reported the therapeutic potential of T3 analogs in lowering lipids, preventing chronic liver disease, and as anticancer agents. Thus, elucidating downstream genes/signaling pathways and molecular mechanisms of TH actions is critical for the treatment of significant public health issues. Here, we have reviewed recent studies focusing on the roles of THs and TRs in several disorders, in particular, liver diseases. We also discuss the potential therapeutic applications of THs and underlying molecular mechanisms.
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24
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Wu SM, Cheng WL, Lin CD, Lin KH. Thyroid hormone actions in liver cancer. Cell Mol Life Sci 2013; 70:1915-36. [PMID: 22955376 PMCID: PMC11113324 DOI: 10.1007/s00018-012-1146-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 08/06/2012] [Accepted: 08/20/2012] [Indexed: 12/13/2022]
Abstract
The thyroid hormone 3,3',5-triiodo-L-thyronine (T3) mediates several physiological processes, including embryonic development, cellular differentiation, metabolism, and the regulation of cell proliferation. Thyroid hormone receptors (TRs) generally act as heterodimers with the retinoid X receptor (RXR) to regulate target genes. In addition to their developmental and metabolic functions, TRs have been shown to play a tumor suppressor role, suggesting that their aberrant expression can lead to tumor transformation. Conversely, recent reports have shown an association between overexpression of wild-type TRs and tumor metastasis. Signaling crosstalk between T3/TR and other pathways or specific TR coregulators appear to affect tumor development. Since TR actions are complex as well as cell context-, tissue- and time-specific, aberrant expression of the various TR isoforms has different effects during diverse tumorigenesis. Therefore, elucidation of the T3/TR signaling mechanisms in cancers should facilitate the identification of novel therapeutic targets. This review provides a summary of recent studies focusing on the role of TRs in hepatocellular carcinomas (HCCs).
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Affiliation(s)
- Sheng-Ming Wu
- Department of Biochemistry, College of Medicine, Chang-Gung University, 259 Wen-hwa 1 Road, Taoyuan, 333 Taiwan
| | - Wan-Li Cheng
- Department of Biochemistry, College of Medicine, Chang-Gung University, 259 Wen-hwa 1 Road, Taoyuan, 333 Taiwan
| | - Crystal D. Lin
- Pre-med Program, Pacific Union College, Angwin, CA 94508 USA
| | - Kwang-Huei Lin
- Department of Biochemistry, College of Medicine, Chang-Gung University, 259 Wen-hwa 1 Road, Taoyuan, 333 Taiwan
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25
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Chen CY, Tsai MM, Chi HC, Lin KH. Biological significance of a thyroid hormone-regulated secretome. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2271-84. [PMID: 23429180 DOI: 10.1016/j.bbapap.2013.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 02/07/2013] [Accepted: 02/11/2013] [Indexed: 01/18/2023]
Abstract
The thyroid hormone, 3,3,5-triiodo-L-thyronine (T3), modulates several physiological processes, including cellular growth, differentiation, metabolism and proliferation, via interactions with thyroid hormone response elements (TREs) in the regulatory regions of target genes. Several intracellular and extracellular protein candidates are regulated by T3. Moreover, T3-regulated secreted proteins participate in physiological processes or cellular transformation. T3 has been employed as a marker in several disorders, such as cardiovascular disorder in chronic kidney disease, as well as diseases of the liver, immune system, endocrine hormone metabolism and coronary artery. Our group subsequently showed that T3 regulates several tumor-related secretory proteins, leading to cancer progression via alterations in extracellular matrix proteases and tumor-associated signaling pathways in hepatocellular carcinomas. Therefore, elucidation of T3/thyroid hormone receptor-regulated secretory proteins and their underlying mechanisms in cancers should facilitate the identification of novel therapeutic targets. This review provides a detailed summary on the known secretory proteins regulated by T3 and their physiological significance. This article is part of a Special Issue entitled: An Updated Secretome.
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Affiliation(s)
- Cheng-Yi Chen
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
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26
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Chi HC, Chen SL, Liao CJ, Liao CH, Tsai MM, Lin YH, Huang YH, Yeh CT, Wu SM, Tseng YH, Chen CY, Tsai CY, Chung IH, Chen WJ, Lin KH. Thyroid hormone receptors promote metastasis of human hepatoma cells via regulation of TRAIL. Cell Death Differ 2012; 19:1802-14. [PMID: 22576662 DOI: 10.1038/cdd.2012.58] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Although accumulating evidence has confirmed the important roles of thyroid hormone (T(3)) and its receptors (TRs) in tumor progression, the specific functions of TRs in carcinogenesis remain unclear. In the present study, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) was directly upregulated by T(3) in TR-overexpressing hepatoma cell lines. TRAIL is an apoptotic inducer, but it can nonetheless trigger non-apoptotic signals favoring tumorigenesis in apoptosis-resistant cancer cells. We found that TR-overexpressing hepatoma cells treated with T(3) were apoptosis resistant, even when TRAIL was upregulated. This apoptotic resistance may be attributable to simultaneous upregulation of Bcl-xL by T(3), because (1) knockdown of T(3)-induced Bcl-xL expression suppressed T(3)-mediated protection against apoptosis, and (2) overexpression of Bcl-xL further protected hepatoma cells from TRAIL-induced apoptotic death, consequently leading to TRAIL-promoted metastasis of hepatoma cells. Moreover, T(3)-enhanced metastasis in vivo was repressed by the treatment of TRAIL-blocking antibody. Notably, TRAIL was highly expressed in a subset of hepatocellular carcinoma (HCC) patients, and this high-level expression was significantly correlated with that of TRs in these HCC tissues. Together, our findings provide evidence for the existence of a novel mechanistic link between increased TR and TRAIL levels in HCC. Thus, TRs induce TRAIL expression, and TRAIL thus synthesized acts in concert with simultaneously synthesized Bcl-xL to promote metastasis, but not apoptosis.
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Affiliation(s)
- H-C Chi
- Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan, Taiwan
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27
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Liao CH, Yeh CT, Huang YH, Wu SM, Chi HC, Tsai MM, Tsai CY, Liao CJ, Tseng YH, Lin YH, Chen CY, Chung IH, Cheng WL, Chen WJ, Lin KH. Dickkopf 4 positively regulated by the thyroid hormone receptor suppresses cell invasion in human hepatoma cells. Hepatology 2012; 55:910-20. [PMID: 21994129 DOI: 10.1002/hep.24740] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 09/27/2011] [Indexed: 01/02/2023]
Abstract
UNLABELLED Thyroid hormone (T(3)) mediates cellular growth, development, and differentiation by binding to the nuclear thyroid hormone receptor (TR). Recent studies suggest that long-term hypothyroidism is associated with human hepatocellular carcinoma (HCC) independent from other major HCC risk factors. Dickkopf (DKK) 4, a secreted protein, antagonizes the Wnt signal pathway. In this study, we demonstrate that T(3) may play a suppressor role by inducing DKK4 expression in HCC cells at both the messenger RNA (mRNA) and protein levels. DKK4 was down-regulated in 67.5% of HCC cancerous tissues. The decrease in DKK4 levels was accompanied by a concomitant decrease in TR protein levels in the matched cancerous tissues in 31% of tissues compared by immunoblotting with the adjacent noncancerous tissues. Further, TR and DKK4 expression levels were positively correlated in both normal and cancerous specimens by tissue array analysis. In function assays, stable DKK4 transfected into J7 or HepG2 cells decreased cell invasion in vitro. Conversely, knocking down DKK4 restores cell invasiveness. DKK4-expressing J7 clones showed increased degradation of β-catenin, but down-regulation of CD44, cyclin D1, and c-Jun. To investigate the effect of DKK4 and TR on tumor growth in vivo, we established a xenograft of J7 cells in nude mice. J7-DKK4 and J7-TRα1 overexpressing mice, which displayed growth arrest, lower lung colony formation index, and smaller tumor size than in control mice, supporting an inhibitory role of DKK4 in tumor progression. CONCLUSION Taken together, these data suggest that the TR/DKK4/Wnt/β-catenin cascade influences the proliferation and migration of hepatoma cells during the metastasis process and support a tumor suppressor role of the TR.
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Affiliation(s)
- Chen-Hsin Liao
- Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan, Taiwan
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28
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Chen CY, Chi LM, Chi HC, Tsai MM, Tsai CY, Tseng YH, Lin YH, Chen WJ, Huang YH, Lin KH. Stable isotope labeling with amino acids in cell culture (SILAC)-based quantitative proteomics study of a thyroid hormone-regulated secretome in human hepatoma cells. Mol Cell Proteomics 2011; 11:M111.011270. [PMID: 22171322 DOI: 10.1074/mcp.m111.011270] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The thyroid hormone, 3, 3',5-triiodo-l-thyronine (T(3)), regulates cell growth, development, differentiation, and metabolism via interactions with thyroid hormone receptors (TRs). However, the secreted proteins that are regulated by T(3) are yet to be characterized. In this study, we used the quantitative proteomic approach of stable isotope labeling with amino acids in cell culture coupled with nano-liquid chromatography-tandem MS performed on a LTQ-Orbitrap instrument to identify and characterize the T(3)-regulated proteins secreted in human hepatocellular carcinoma cell lines overexpressing TRα1 (HepG2-TRα1). In total, 1742 and 1714 proteins were identified and quantified, respectively, in three independent experiments. Among these, 61 up-regulated twofold and 11 down-regulated twofold proteins were identified. Eight proteins displaying increased expression and one with decreased expression in conditioned media were validated using Western blotting. Real-time quantitative RT-PCR further disclosed induction of plasminogen activator inhibitor-1 (PAI-1), a T(3) target, in a time-course and dose-dependent manner. Serial deletions of the PAI-1 promoter region and subsequent chromatin immunoprecipitation assays revealed that the thyroid hormone response element on the promoter is localized at positions -327/-312. PAI-1 overexpression enhanced tumor growth and migration in a manner similar to what was seen when T(3) induced PAI-1 expression in J7-TRα1 cells, both in vitro and in vivo. An in vitro neutralizing assay further supported a crucial role of secreted PAI-1 in T(3)/TR-regulated cell migration. To our knowledge, these results demonstrate for the first time that proteins involved in the urokinase plasminogen activator system, including PAI-1, uPAR, and BSSP4, are augmented in the extra- and intracellular space of T(3)-treated HepG2-TRα1 cells. The T(3)-regulated secretome generated in the current study may provide an opportunity to establish the mechanisms underlying T(3)-associated tumor progression and prognosis.
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Affiliation(s)
- Cheng-Yi Chen
- Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan, Taiwan 333
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29
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Rosen MD, Chan IH, Privalsky ML. Mutant thyroid hormone receptors (TRs) isolated from distinct cancer types display distinct target gene specificities: a unique regulatory repertoire associated with two renal clear cell carcinomas. Mol Endocrinol 2011; 25:1311-25. [PMID: 21622534 DOI: 10.1210/me.2010-0420] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Thyroid hormone receptors (TRs) are hormone-regulated transcription factors that regulate a diverse array of biological activities, including metabolism, homeostasis, and development. TRs also serve as tumor suppressors, and aberrant TR function (via mutation, deletion, or altered expression) is associated with a spectrum of both neoplastic and endocrine diseases. A particularly high frequency of TR mutations has been reported in renal clear cell carcinoma (RCCC) and in hepatocellular carcinoma (HCC). We have shown that HCC-TR mutants regulate only a fraction of the genes targeted by wild-type TRs but have gained the ability to regulate other, unique, targets. We have suggested that this altered gene recognition may contribute to the neoplastic phenotype. Here, to determine the generality of this phenomenon, we examined a distinct set of TR mutants associated with RCCC. We report that two different TR mutants, isolated from independent RCCC tumors, possess greatly expanded target gene specificities that extensively overlap one another, but only minimally overlap that of the wild-type TRs, or those of two HCC-TR mutants. Many of the genes targeted by either or both RCCC-TR mutants have been previously implicated in RCCC and include a series of metallothioneins, solute carriers, and genes involved in glycolysis and energy metabolism. We propose as a hypothesis that TR mutations from RCCC and HCC may play tissue-specific roles in carcinogenesis, and that the divergent target gene recognition patterns of TR mutants isolated from the two different types of tumors may arise from different selective pressures during development of RCCC vs. HCC.
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Affiliation(s)
- Meghan D Rosen
- Department of Microbiology, College of Biological Sciences, University of California at Davis, Davis, California 95616, USA
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30
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Bondzi C, Brunner AM, Munyikwa MR, Connor CD, Simmons AN, Stephens SL, Belt PA, Roggero VR, Mavinakere MS, Hinton SD, Allison LA. Recruitment of the oncoprotein v-ErbA to aggresomes. Mol Cell Endocrinol 2011; 332:196-212. [PMID: 21075170 PMCID: PMC4634111 DOI: 10.1016/j.mce.2010.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Accepted: 10/14/2010] [Indexed: 02/01/2023]
Abstract
Aggresome formation, a cellular response to misfolded protein aggregates, is linked to cancer and neurodegenerative disorders. Previously we showed that Gag-v-ErbA (v-ErbA), a retroviral variant of the thyroid hormone receptor (TRα1), accumulates in and sequesters TRα1 into cytoplasmic foci. Here, we show that foci represent v-ErbA targeting to aggresomes. v-ErbA colocalizes with aggresomal markers, proteasomes, hsp70, HDAC6, and mitochondria. Foci have hallmark characteristics of aggresomes: formation is microtubule-dependent, accelerated by proteasome inhibitors, and they disrupt intermediate filaments. Proteasome-mediated degradation is critical for clearance of v-ErbA and T(3)-dependent TRα1 clearance. Our studies highlight v-ErbA's complex mode of action: the oncoprotein is highly mobile and trafficks between the nucleus, cytoplasm, and aggresome, carrying out distinct activities within each compartment. Dynamic trafficking to aggresomes contributes to the dominant negative activity of v-ErbA and may be enhanced by the viral Gag sequence. These studies provide insight into novel modes of oncogenesis across multiple cellular compartments.
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Affiliation(s)
- Cornelius Bondzi
- Department of Biological Sciences, Hampton University, Hampton, VA 23668
| | - Abigail M. Brunner
- Department of Biology, College of William and Mary, Williamsburg, VA 23187
| | | | - Crystal D. Connor
- Department of Biological Sciences, Hampton University, Hampton, VA 23668
| | - Alicia N. Simmons
- Department of Biological Sciences, Hampton University, Hampton, VA 23668
| | | | - Patricia A. Belt
- Department of Biological Sciences, Hampton University, Hampton, VA 23668
| | - Vincent R. Roggero
- Department of Biology, College of William and Mary, Williamsburg, VA 23187
| | | | - Shantá D. Hinton
- Department of Biology, College of William and Mary, Williamsburg, VA 23187
| | - Lizabeth A. Allison
- Department of Biology, College of William and Mary, Williamsburg, VA 23187
- Corresponding author: Lizabeth A. Allison, Department of Biology, College of William and Mary, Integrated Science Center Room 3035B, 540 Landrum Drive, Williamsburg, VA 23187, Tele: 757-221-2232, Fax: 757-221-6483,
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31
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Chan IH, Privalsky ML. A conserved lysine in the thyroid hormone receptor-alpha1 DNA-binding domain, mutated in hepatocellular carcinoma, serves as a sensor for transcriptional regulation. Mol Cancer Res 2010; 8:15-23. [PMID: 20053725 DOI: 10.1158/1541-7786.mcr-09-0425] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nuclear receptors are hormone-regulated transcription factors that play key roles in normal physiology and development; conversely, mutant nuclear receptors are associated with a wide variety of neoplastic and endocrine disorders. Typically, these receptor mutants function as dominant negatives and can interfere with wild-type receptor activity. Dominant-negative thyroid hormone receptor (TR) mutations have been identified in over 60% of the human hepatocellular carcinomas analyzed. Most of these mutant TRs are defective for corepressor release or coactivator binding in vitro, accounting for their transcriptional defects in vivo. However, two HCC-TR mutants that function as dominant-negative receptors in cells display near-normal properties in vitro, raising questions about the molecular basis behind their transcriptional defects. We report here that a single amino acid substitution, located at the same position in the DNA-binding domain of both mutants, is responsible for their impaired transcriptional activation and dominant-negative properties. Significantly, this amino acid, K74 in TRalpha, is highly conserved in all known nuclear receptors and seems to function as an allosteric sensor that regulates the transcriptional activity of these receptors in response to binding to their DNA recognition sequences. We provide evidence that these two human hepatocellular carcinoma mutants have acquired dominant-negative function as a result of disruption of this allosteric sensing. Our results suggest a novel mechanism by which nuclear receptors can acquire transcriptional defects and contribute to neoplastic disease.
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Affiliation(s)
- Ivan H Chan
- Department of Microbiology, One Shields Avenue, University of California at Davis, Davis, CA 95616, USA
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