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Fan Y, Zheng X, Xu T, Li P, Zhang Y, Ran Y, Wei T. A bibliometric analysis of follicular thyroid carcinoma: Current situation, hot spots, and global trends. Asian J Surg 2024:S1015-9584(24)01644-0. [PMID: 39117545 DOI: 10.1016/j.asjsur.2024.07.271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 06/26/2024] [Accepted: 07/22/2024] [Indexed: 08/10/2024] Open
Abstract
BACKGROUND Follicular thyroid carcinoma (FTC), the second most prevalent thyroid cancer after papillary thyroid cancer (PTC), tends to metastasize distantly, leading to poorer outcomes. Despite substantial research, a holistic bibliometric analysis of FTC literature is lacking. This study aims to fill this gap by employing bibliometric methods to track FTC research evolution. METHODS English FTC publications were systematically gathered from the Web of Science. Bibliometric analysis, using R, VOSviewer, CiteSpace, and Excel, synthesized data and explored global research trends and topics. RESULTS From 2000 to 2023, 9086 authors from 1953 institutions across 75 countries contributed to 1776 papers in 491 academic journals on FTC. The last two decades have witnessed a steady increase in publications related to FTC, with the United States leading in terms of publication volume. The United States dominated both in publications and citations, with the National Cancer Institute and Sheue-Yann Cheng as leading contributors. The journal 'Thyroid' featured the most publications, while the 'Journal of Clinical Endocrinology and Metabolism' ranked highest in citation frequency. Research focused on gene expression analysis and preoperative diagnostics, with recent trends shifting toward prognosis management and machine learning due to advances in medical technology and increased health awareness. CONCLUSION This comprehensive bibliometric analysis has mapped the landscape of FTC research, highlighting key contributors, institutions, and thematic trends. Current discourse predominantly revolves around genetic analysis, prognostic determinants, and preoperative diagnostics in FTC. This foundational work guides future FTC research, providing insights into its evolution.
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Affiliation(s)
- Yuanyuan Fan
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Xun Zheng
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tianfeng Xu
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Pengyu Li
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Yujie Zhang
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Yanhao Ran
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tao Wei
- Division of Thyroid Surgery, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, China.
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2
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Xu B. Molecular alterations of follicular cell-derived thyroid neoplasms. DIAGNOSTIC HISTOPATHOLOGY 2023. [DOI: 10.1016/j.mpdhp.2023.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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3
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Gajzer DC, Tjendra Y, Kerr DA, Algashaamy K, Zuo Y, Menendez SG, Jorda M, Garcia-Buitrago M, Gomez-Fernandez C, Velez Torres JM. Probability of malignancy as determined by ThyroSeq v3 genomic classifier varies according to the subtype of atypia. Cancer Cytopathol 2022; 130:881-890. [PMID: 35775861 DOI: 10.1002/cncy.22617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/21/2022] [Accepted: 05/31/2022] [Indexed: 11/12/2022]
Abstract
BACKGROUND ThyroSeq assesses the probability of malignancy (POM) in thyroid fine-needle aspiration cytology specimens diagnosed as atypia of undetermined significance (AUS). The authors investigated whether defined AUS subcategories are associated with specific molecular alterations, the molecular-derived risk of malignancy (MDROM), and the risk of malignancy (ROM). METHODS Fine-needle aspiration cytology reports of AUS and corresponding results from the ThyroSeq version 3 genomic classifier results were retrieved and subcategorized as follicular cells with either cytologic atypia (FC-C), architectural atypia (FC-A), both cytologic and architectural atypia (FC-CA), or a predominance of Hurthle cells (PHC). The MDROM, ROM, and frequency of molecular alterations by subcategory were computed and analyzed, and p < .05 was considered significant. RESULTS The final analysis included 541 cases subdivided into 233 with FC-A, 104 with FC-C, 116 with FC-CA, and 88 with PHC. The benign call rate and positive call rate for the AUS category were 72% and 28%, respectively, which varied between AUS subcategories. The MDROM by subcategory was 15.9% FC-A, 20.5% FC-C, 33.8% FC-CA, and 14.4% PHC. Histologic follow-up was available for 155 (28%) AUS cases with a follow-up period ≥12 months. The 95% confidence intervals of the MDROMs overlapped with the ROMs. The highest MDROM and ROM were in the FC-CA subcategory. RAS mutations were present in all subcategories. BRAF V600E mutations and papillary thyroid carcinoma were most frequent in the FC-CA subcategory. Noninvasive follicular thyroid neoplasm with papillary-like nuclear features was significantly more frequent in the FC-C subcategory. CONCLUSIONS The current results demonstrated that AUS subcategories are associated with specific genetic alterations, the MDROM, and the ROM. Molecular results and an awareness of various cancer probabilities within AUS subcategories can allow for a more tailored management.
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Affiliation(s)
- David C Gajzer
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA.,Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Youley Tjendra
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Darcy A Kerr
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center and Geisel School of Medicine, Lebanon, New Hampshire, USA
| | - Khaled Algashaamy
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Yiqin Zuo
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Silvia Gra Menendez
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Merce Jorda
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Monica Garcia-Buitrago
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Carmen Gomez-Fernandez
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Jaylou M Velez Torres
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
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Kim D, Jung SH, Chung YJ. Screening of novel alkaloid inhibitors for vascular endothelial growth factor in cancer cells: an integrated computational approach. Genomics Inform 2021; 19:e41. [PMID: 35172474 PMCID: PMC8752984 DOI: 10.5808/gi.21061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 11/12/2021] [Indexed: 11/20/2022] Open
Abstract
In addition to mutations and copy number alterations, gene fusions are commonly identified in cancers. In thyroid cancer, fusions of important cancer-related genes have been commonly reported; however, extant panels do not cover all clinically important gene fusions. In this study, we aimed to develop a custom RNA-based sequencing panel to identify the key fusions in thyroid cancer. Our ThyChase panel was designed to detect 87 types of gene fusion. As quality control of RNA sequencing, five housekeeping genes were included in this panel. When we applied this panel for the analysis of fusions containing reference RNA (HD796), three expected fusions (EML4-ALK, CCDC6-RET, and TPM3-NTRK1) were successfully identified. We confirmed the fusion breakpoint sequences of the three fusions from HD796 by Sanger sequencing. Regarding the limit of detection, this panel could detect the target fusions from a tumor sample containing a 1% fusion-positive tumor cellular fraction. Taken together, our ThyChase panel would be useful to identify gene fusions in the clinical field.
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Affiliation(s)
- Dongmoung Kim
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul 06591, Korea
| | - Seung-Hyun Jung
- Department of Biochemistry, The Catholic University of Korea, Seoul 06591, Korea.,Precision Medicine Research Center, Integrated Research Center for Genome Polymorphism, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Yeun-Jun Chung
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul 06591, Korea.,Precision Medicine Research Center, Integrated Research Center for Genome Polymorphism, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea.,Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
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Odate T, Oishi N, Vuong HG, Mochizuki K, Kondo T. Genetic differences in follicular thyroid carcinoma between Asian and Western countries: a systematic review. Gland Surg 2020; 9:1813-1826. [PMID: 33224857 DOI: 10.21037/gs-20-356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Thyroid cancer is the most common endocrine malignancy, and follicular thyroid carcinoma (FTC) is the second most common thyroid cancer following papillary thyroid carcinoma (PTC). RAS mutation and PAX8/PPARγ rearrangement are the two representative genetic alterations in FTC, and there are studies from various countries on their regional frequencies. In this study, we systematically reviewed all available literature aiming to create a complete global map showing the frequencies of these common oncogenic drivers in FTC and to highlight the trends in Asian and Western countries. We performed a search in two electronic databases and identified 71 studies that fit our criteria from 1,329 studies found with our database search terms. There were 54 articles with 1,143 FTC patients and 39 articles with 764 FTC patients available for calculating the frequency of RAS mutation and PAX8/PPARγ rearrangement, respectively. NRAS mutation was the most frequent RAS mutation in all regions, followed by HRAS and KRAS mutation. The frequency of RAS mutation in Asian countries was higher than Western countries (34% vs. 27%, P=0.006) when the mutation detection method was not taken into account. In contrast, this difference in RAS mutation incidence between Asian and Western countries (28% vs. 25%, P=0.47) did not show up in our subgroup analysis incorporating only studies using direct sequencing method. The reported difference of RAS mutation frequency in the previous literature might not be due to the true prevalence of RAS mutation. They could be attributed to the difference in the detection method. As to PAX8/PPARγ rearrangement, Western countries overall had a much higher prevalence than Asian countries (23% vs. 4%, P<0.001), but some European countries had a low incidence, implying regional heterogeneity of PAX8/PPARγ rearrangement. A substantial lack of mutation data in FTC was found in several regions of the world such as Central Asia, Middle East, Africa, and Central and South America. Our results provide the most comprehensive global status of representative genetic alterations in FTC and highlight the similarities and differences between Asian and Western countries.
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Affiliation(s)
- Toru Odate
- Department of Pathology, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Naoki Oishi
- Department of Pathology, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Huy Gia Vuong
- Department of Pathology, Oklahoma University Health Sciences Center, Oklahoma City, OK, USA
| | - Kunio Mochizuki
- Department of Pathology, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Tetsuo Kondo
- Department of Pathology, University of Yamanashi, Chuo, Yamanashi, Japan
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Boufraqech M, Nilubol N. Multi-omics Signatures and Translational Potential to Improve Thyroid Cancer Patient Outcome. Cancers (Basel) 2019; 11:E1988. [PMID: 31835496 PMCID: PMC6966476 DOI: 10.3390/cancers11121988] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 12/03/2019] [Indexed: 02/07/2023] Open
Abstract
Recent advances in high-throughput molecular and multi-omics technologies have improved our understanding of the molecular changes associated with thyroid cancer initiation and progression. The translation into clinical use based on molecular profiling of thyroid tumors has allowed a significant improvement in patient risk stratification and in the identification of targeted therapies, and thereby better personalized disease management and outcome. This review compiles the following: (1) the major molecular alterations of the genome, epigenome, transcriptome, proteome, and metabolome found in all subtypes of thyroid cancer, thus demonstrating the complexity of these tumors and (2) the great translational potential of multi-omics studies to improve patient outcome.
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Affiliation(s)
| | - Naris Nilubol
- Surgical Oncology Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20817, USA;
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7
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Thyroid tumors with follicular architecture. Ann Diagn Pathol 2019; 38:51-58. [DOI: 10.1016/j.anndiagpath.2018.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 10/17/2018] [Indexed: 11/19/2022]
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Abstract
BACKGROUND Gene fusions are known in many cancers as driver or passenger mutations. They play an important role in both the etiology and pathogenesis of cancer and are considered as potential diagnostic and prognostic markers and possible therapeutic targets. The spectrum and prevalence of gene fusions in thyroid cancer ranges from single cases up to 80%, depending on the specific type of cancer. During last three years, massive parallel sequencing technologies have revealed new fusions and allowed detailed characteristics of fusions in different types of thyroid cancer. SUMMARY This article reviews all known fusions and their prevalence in papillary, poorly differentiated and anaplastic, follicular, and medullary carcinomas. The mechanisms of fusion formation are described. In addition, the mechanisms of oncogenic transformation, such as altered gene expression, forced oligomerization, and subcellular localization, are given. CONCLUSION The prognostic value and perspectives of the utilization of gene fusions as therapeutic targets are discussed.
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Affiliation(s)
- Valentina D Yakushina
- 1 Research Centre for Medical Genetics , Moscow, Russian Federation
- 2 Moscow Institute of Physics and Technology , Moscow, Russian Federation
| | | | - Alexander V Lavrov
- 1 Research Centre for Medical Genetics , Moscow, Russian Federation
- 4 Russian National Research Medical University , Moscow, Russian Federation
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Giordano TJ. Genomic Hallmarks of Thyroid Neoplasia. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2017; 13:141-162. [PMID: 29083981 DOI: 10.1146/annurev-pathol-121808-102139] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The genomic landscape of thyroid cancers that are derived from follicular cells has been substantially elucidated through the coordinated application of high-throughput genomic technologies. Here, I review the common genetic alterations across the spectrum of thyroid neoplasia and present the resulting model of thyroid cancer initiation and progression. This model illustrates the striking correlation between tumor differentiation and overall somatic mutational burden, which also likely explains the highly variable clinical behavior and outcome of patients with thyroid cancers. These advances are yielding critical insights into thyroid cancer pathogenesis, which are being leveraged for the development of new diagnostic tools, prognostic and predictive biomarkers, and novel therapeutic approaches.
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Affiliation(s)
- Thomas J Giordano
- Departments of Pathology and Internal Medicine, Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA;
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10
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Sharifah NASH, Zakaria Z, Chia WK. FISH analysis using PPAR γ-specific probes for detection of PAX8-PPAR γ translocation in follicular thyroid neoplasms. Methods Mol Biol 2013; 952:187-196. [PMID: 23100233 DOI: 10.1007/978-1-62703-155-4_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Fluorescence in situ hybridization (FISH) is increasingly gaining importance in clinical diagnostics settings. Due to the ability of the technique to detect chromosomal abnormalities in samples with low cellularity or containing a mixed population of cells even at a single-cell level, it has become more popular in cancer research and diagnosis. Here, we describe the FISH technique for detection of PAX8-PPARγ translocation in follicular thyroid neoplasms, and the optimal protocol for the detection of this fusion gene using in archival formalin-fixed paraffin-embedded (FFPE) thyroid tissue sections.
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Abstract
Recurrent gene fusions have been thought to play a central role in leukemias, lymphomas, and sarcomas, but they have been neglected in carcinomas, largely because of technical limitations of cytogenetics. In the past few years, an increasing number of recurrent gene fusions have been recognized in epithelial cancers. The majority of prostate cancers, for example, have an androgen-regulated fusion of one of the ETS transcription factor gene family. Notably, the fusion genes can often serve as specific diagnostic markers, criteria of molecular classification and therefore potential therapeutic targets. Recent studies have focused on investigations of morphologic features (phenotype) of recurrent gene fusions (genotype) in malignancies. In this review, we will summarize the histologic features of known recurrent genomic rearrangements in carcinomas, especially focusing on TMPRSS2-ERG fusion in prostate cancer, EML4-ALK in lung cancer, ETV6-NTRK3 in secretory breast cancer, RET/PTC and PAX8/PPARγ1 rearrangements in thyroid cancer. In addition, we will describe how these features could potentially be used to alert the pathologists of the diagnosis of fusion-positive tumor. A combination of histologic validation with other screening strategies (eg, immunohistochemistry) for recognition of recurrent gene fusions is also highlighted.
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de Vries MM, Celestino R, Castro P, Eloy C, Máximo V, van der Wal JE, Plukker JTM, Links TP, Hofstra RMW, Sobrinho-Simões M, Soares P. RET/PTC rearrangement is prevalent in follicular Hürthle cell carcinomas. Histopathology 2012; 61:833-43. [PMID: 22803838 DOI: 10.1111/j.1365-2559.2012.04276.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
AIMS The molecular alterations underlying follicular Hürthle cell carcinomas (FHCCs) are largely unknown. In an attempt to clarify this issue, we analysed a series of Hürthle cell tumours for the presence of RET/PTC and PAX8/PPARG rearrangements and BRAF, HRAS and NRAS mutations. METHODS AND RESULTS We investigated a series of 20 follicular Hürthle cell tumours [17 FHCCs and three follicular Hürthle cell adenomas (FHCAs)]. RET/PTC rearrangements were found in 33% of FHCAs and in 38% of FHCCs. All RET/PTC-positive FHCCs had a solid pattern of growth. PAX8/PPARG rearrangement was present in 27% of the FHCCs which displayed, in most cases, a follicular architecture. NRAS mutation was detected in one FHCC. An FHCC with a solid/microfollicular growth pattern scored positive for both RET/PTC and PAX8/PPARG rearrangement. CONCLUSIONS Our study has shown a significant association between RET/PTC rearrangements and FHCCs with a solid growth pattern, thus raising the possibility of using tyrosine kinase inhibitors for the treatment of patients with FHCCs, which are often refractory to radioiodine treatment.
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Affiliation(s)
- Margriet M de Vries
- Department of Genetics, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
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Identification of novel Pax8 targets in FRTL-5 thyroid cells by gene silencing and expression microarray analysis. PLoS One 2011; 6:e25162. [PMID: 21966443 PMCID: PMC3179481 DOI: 10.1371/journal.pone.0025162] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/26/2011] [Indexed: 02/07/2023] Open
Abstract
Background The differentiation program of thyroid follicular cells (TFCs), by far the most abundant cell population of the thyroid gland, relies on the interplay between sequence-specific transcription factors and transcriptional coregulators with the basal transcriptional machinery of the cell. However, the molecular mechanisms leading to the fully differentiated thyrocyte are still the object of intense study. The transcription factor Pax8, a member of the Paired-box gene family, has been demonstrated to be a critical regulator required for proper development and differentiation of thyroid follicular cells. Despite being Pax8 well-characterized with respect to its role in regulating genes involved in thyroid differentiation, genomics approaches aiming at the identification of additional Pax8 targets are lacking and the biological pathways controlled by this transcription factor are largely unknown. Methodology/Principal Findings To identify unique downstream targets of Pax8, we investigated the genome-wide effect of Pax8 silencing comparing the transcriptome of silenced versus normal differentiated FRTL-5 thyroid cells. In total, 2815 genes were found modulated 72 h after Pax8 RNAi, induced or repressed. Genes previously reported to be regulated by Pax8 in FRTL-5 cells were confirmed. In addition, novel targets genes involved in functional processes such as DNA replication, anion transport, kinase activity, apoptosis and cellular processes were newly identified. Transcriptome analysis highlighted that Pax8 is a key molecule for thyroid morphogenesis and differentiation. Conclusions/Significance This is the first large-scale study aimed at the identification of new genes regulated by Pax8, a master regulator of thyroid development and differentiation. The biological pathways and target genes controlled by Pax8 will have considerable importance to understand thyroid disease progression as well as to set up novel therapeutic strategies.
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Klemke M, Drieschner N, Laabs A, Rippe V, Belge G, Bullerdiek J, Sendt W. On the prevalence of the PAX8-PPARG fusion resulting from the chromosomal translocation t(2;3)(q13;p25) in adenomas of the thyroid. Cancer Genet 2011; 204:334-9. [PMID: 21763631 DOI: 10.1016/j.cancergen.2011.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 04/28/2011] [Accepted: 05/03/2011] [Indexed: 11/16/2022]
Abstract
The chromosomal translocation t(2;3)(q13;p25) characterizes a subgroup of tumors originating from the thyroid follicular epithelium and was initially discovered in a few cases of adenomas. Later, a fusion of the genes PAX8 and PPARG resulting from this translocation was frequently observed in follicular carcinomas and considered as a marker of follicular thyroid cancer. According to subsequent studies, however, this rearrangement is not confined to carcinomas but also occurs in adenomas, with considerably varying frequencies. Only five cases of thyroid adenomas with this translocation detected by conventional cytogenetics have been documented. In contrast, studies using reverse-transcription polymerase chain reaction (RT-PCR) detected fusion transcripts resulting from that translocation in an average of 8.2% of adenomas. The aim of this study was to determine the frequency of the PAX8-PPARG fusion in follicular adenomas and to use the HMGA2 mRNA level of such tumors as an indicator of malignancy. In cytogenetic studies of 192 follicular adenomas, the t(2;3)(q13;p25) has been identified in only two cases described herein. Histopathology revealed no evidence of malignancy in either case, and, concordantly, HMGA2 mRNA levels were not elevated. In summary, the fusion is a rare event in follicular adenomas and its prevalence may be overestimated in many RT-PCR-based studies.
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Affiliation(s)
- Markus Klemke
- Center for Human Genetics, University of Bremen, Germany
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