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Zhou Y, El-Bahrawy M. Gene fusions in tumourigenesis with particular reference to ovarian cancer. J Med Genet 2021; 58:789-795. [PMID: 34462289 DOI: 10.1136/jmedgenet-2021-108010] [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: 06/02/2021] [Accepted: 08/11/2021] [Indexed: 11/04/2022]
Abstract
Gene fusion, a genomic event that generates a novel gene from two independent genes, has long been known to be implicated in tumourigenesis and cancer progression. It has thus served as a diagnostic and prognostic biomarker in cancer, as well as an ideal therapeutic target in cancer therapy. Gene fusion can arise from chromosomal rearrangement and alternative splicing of transcripts, resulting in deregulation of proto-oncogenes or creation of an oncogenic novel gene. Largely facilitated by next generation sequencing technologies, a plethora of novel gene fusions have been identified in a variety of cancers, which leaves us the challenge of functionally characterising these candidate gene fusions. In this review, we summarise the molecular mechanisms, the oncogenic consequences and the therapeutic implications of verified gene fusions. We also discuss recent studies on gene fusions in both common and rare subtypes of ovarian tumours and how these findings can be translated to cancer therapies to benefit patients carrying these gene fusions.
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Affiliation(s)
- Yi Zhou
- Surgery and Cancer, Imperial College London, London, UK
| | - Mona El-Bahrawy
- Metabolism, Digestion and Reproduction, Imperial College London, London, UK .,Pathology, Alexandria University Faculty of Medicine, Alexandria, Egypt
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Diagnostic Value of TROP2 Expression in Papillary Thyroid Carcinoma. Appl Immunohistochem Mol Morphol 2020; 29:218-222. [PMID: 33264108 DOI: 10.1097/pai.0000000000000886] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/14/2020] [Indexed: 01/22/2023]
Abstract
Papillary thyroid carcinoma (PTC) represents the most common primary malignant thyroid lesion in all age groups. As diagnosis of PTC could be challenging in some cases and borderline nuclear features could be seen in some benign mimickers, several immunohistochemical markers are proposed to be helpful for making the correct diagnosis. In this study the authors investigated the diagnostic value of transmembrane glycoprotein (TROP2) for differentiating PTC from other thyroid follicular lesions. A total of 155 total thyroidectomy specimens including 84 cases of PTC and 71 cases of non-PTC were investigated. Among non-PTC group, 45 cases were follicular neoplasms and 26 cases were Hashimoto thyroiditis. TROP2 expression was observed in 82 of 84 cases of PTC group. In contrast only 5 cases of non-PTC group, all from Hashimoto thyroiditis specimens, showed positive expression. The sensitivity, specificity, positive predictive value, and negative predictive value of TROP2 for diagnosis of PTC was 98%, 93%, 94%, and 97%, respectively. The authors concluded that high sensitivity and specificity of TROP2 as well as its uniform negative reaction in follicular adenoma and carcinoma makes it a valuable immunohistochemical marker for diagnosis of PTC.
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Abdou AG, Shabaan M, Abdallha R, Nabil N. Diagnostic Value of TROP-2 and CK19 Expression in Papillary Thyroid Carcinoma in Both Surgical and Cytological Specimens. CLINICAL PATHOLOGY (THOUSAND OAKS, VENTURA COUNTY, CALIF.) 2019; 12:2632010X19863047. [PMID: 31384753 PMCID: PMC6647210 DOI: 10.1177/2632010x19863047] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 06/18/2019] [Indexed: 12/29/2022]
Abstract
Papillary thyroid carcinoma (PTC) represents the most common primary malignant thyroid tumor and its diagnosis is dependent on the presence of classic nuclear features that are sometimes seen in some non-neoplastic and benign lesions. Several immunohistochemical markers are used individually or in combination to help in differentiation of PTC from mimickers. The aim of the current study was to assess the diagnostic value of TROP-2 and cytokeratin 19 (CK19) expression in differentiating PTC from other mimickers both singly and in combination. The current study was carried out on 77 surgical specimens (56 PTC and 21 non-neoplastic cases) and 12 cytological specimens (4 THY2, 6 THY4, and 2 THY5). TROP-2 was negative in 81% of non-neoplastic surgical specimens and in 100% of THY2 cytological specimens while it was positive in 71.4% of PTC surgical specimens and 100% of THY4/THY5 cytological specimens. Sensitivity and specificity of TROP-2 positive expression for diagnosis of PTC in surgical specimens reached 71% and 81%, respectively, while it reached 100% for both in cytological specimens. Cytokeratin 19 showed positive expression in 85.7% of non-neoplastic surgical specimens and in 92.9% of PTC surgical specimens. Cytokeratin 19 showed negative expression in 75% of Thy2 cases while it was positive in all studied Thy4 and Thy5 cases. Sensitivity and specificity of CK19 total estimated score for diagnosis of PTC in surgical specimens were 78.6% and 66.7%, respectively, while it reached 100% and 75% in cytological specimens. Positive TROP-2 and CK19 expression in PTC were associated with lymph node metastasis. TROP-2 is a specific rather than sensitive marker while CK19 is a sensitive rather than specific marker in differentiating PTC from other mimickers in surgical specimens. The diagnostic validity of both markers was superior in diagnosis of classic PTC compared with follicular variant PTC. TROP-2 is superior to CK19 in diagnosis of PTC in cytological specimens. Both TROP-2 and CK19 could be used preoperatively in adjunct to hematoxylin and eosin for more confident diagnosis of thyroid cytology and along with radiology as predictors of lymph node metastasis.
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Affiliation(s)
- Asmaa Gaber Abdou
- Department of Pathology, Faculty of Medicine, Menoufia University, Shebein Elkom, Egypt
| | - Mohammed Shabaan
- Department of Pathology, Faculty of Medicine, Menoufia University, Shebein Elkom, Egypt
| | - Rania Abdallha
- Department of Pathology, Faculty of Medicine, Menoufia University, Shebein Elkom, Egypt
| | - Nehal Nabil
- Department of Pathology, Faculty of Medicine, Menoufia University, Shebein Elkom, Egypt
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Cheng H, Yang L, Xiong J, Peng J, Ruan Q. Multiple thyroid nodules in the lung: metastasis or ectopia? Diagn Pathol 2015; 10:61. [PMID: 26047938 PMCID: PMC4458025 DOI: 10.1186/s13000-015-0299-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 05/12/2015] [Indexed: 11/13/2022] Open
Abstract
Background Intrapulmonary thyroid tissue with no malignant history of the thyroid gland is extremely rare. Usually, it is interpreted as ectopic thyroid tissue. Here we describe a case of bilateral pulmonary thyroid nodules with a history of multinodular thyroid goiter. History A 37-year-old female had recurrent multinodular thyroid goiter and showed bilateral pulmonary nodules on CT scan. Video-assisted thoracic surgery (VATS) was performed for the largest nodule biopsy. Pathological and molecular examinations were done after biopsy, and both were shown the characters of benign thyroid tissues. To eliminate the possibility of thyroid carcinoma metastases, total thyroidectomy with modified radical neck dissection was performed, and there were no malignant pathological findings. After surgery, this patient accepted adjuvant radiometabolic treatment for ablation of the remaining intrapulmonary nodules. Her thyroglobulin level decreased to an undetectable level, and she has currently survived for 24 months after surgery. Clinical significance In this case, pulmonary ectopic thyroid and metastasizing thyroid carcinoma should both be considered, but the metastatic pattern and benign pathological characters were inconsistent with any of the corresponding diagnosis. Ultimately, this patient accepted postoperative treatment of thyroid carcinoma metastasis. Conclusions This is a rare thyroid disease with malignant behavior but no pathological evidence. Careful diagnosis and postoprative follow-up should be carried out whenever such nodules are encountered in clinical practice. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1255194331453728.
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Affiliation(s)
- Henghui Cheng
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Dadao, Wuhan, 430030, People's Republic of China.
| | - Lili Yang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Dadao, Wuhan, 430030, People's Republic of China.
| | - Jing Xiong
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Dadao, Wuhan, 430030, People's Republic of China.
| | - Jian Peng
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
| | - Qiurong Ruan
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Dadao, Wuhan, 430030, People's Republic of China.
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Şahpaz A, Önal B, Yeşilyurt A, Han Ü, Delibaşı T. BRAF(V600E) Mutation, RET/PTC1 and PAX8-PPAR Gamma Rearrangements in Follicular Epithelium Derived Thyroid Lesions - Institutional Experience and Literature Review. Balkan Med J 2015; 32:156-66. [PMID: 26167339 DOI: 10.5152/balkanmedj.2015.15101] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 12/08/2014] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Thyroid cancers are the most frequently occurring endocrine malignancy worldwide. In Turkey, thyroid cancers are ranked 2(nd) on the incidence list in women, with a rate of 16.2%, but they are not included among the top 10 cancer types in men. AIMS To identify the contribution of the BRAF(V600E) mutation, and the RET/PTC1 and PAX8-PPARγ rearrangements in the diagnosis and differential diagnosis of follicular epithelial-derived thyroid lesions. STUDY DESIGN Retrospective clinical and molecular genetic study. METHODS A total of 86 thyroid cases diagnosed between 2001 and 2012 at the Department of Pathology were included in the retrospective study group. Samples best representing the lesion and comprising capsules were chosen in the selection of paraffin blocks pertaining to the cases. The BRAF(V600E) mutation, and the RET/PTC1 and PAX8-PPARγ rearrangements were investigated in all cases. RESULTS The BRAF(V600E) mutation was observed in 12 out of 37 papillary carcinoma cases (32.4%), in 1 out of 15 follicular carcinoma cases (6.6%), and in 1 out of 7 undifferentiated carcinoma cases (14.3%). No mutation was detected in benign lesions. The RET/PTC1 rearrangement was detected in 2 out of 7 undifferentiated carcinoma cases (28.6%), and in 1 out of 15 follicular carcinoma cases (6.6%). No gene rearrangement was detected in benign lesions. The PAX8-PPARγ rearrangement was detected in 5 out of 15 follicular thyroid carcinoma cases (33.3%) and in 1 out of 15 follicular adenoma cases (6.6%). CONCLUSION The BRAF(V600E) mutation and RET/PTC1 rearrangement were effective in distinguishing the follicular epithelium-derived benign and malignant lesions of the thyroid in the resection materials. The BRAF(V600E) mutation was rather specific to papillary carcinoma in the thyroid, and in cases where the BRAF(V600E) mutation was detected, multi-centricity, lymph node metastasis and capsular invasion findings were observed more frequently compared to cases in which no mutation was observed. The PAX8-PPARγ rearrangement was observed to be more effective in the differentiation of adenomas and carcinomas in follicular neoplasms of the thyroid, whereas the RET/PTC1 analysis contributed to the differential diagnosis of papillary carcinoma histogenesis at a frequency of 29% in undifferentiated thyroid carcinomas.
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Affiliation(s)
- Ahmet Şahpaz
- Department of Pathology & Cytology, Ankara Dışkapı Training and Research Hospital, Ankara, Turkey
| | - Binnur Önal
- Department of Pathology & Cytology, Ankara Dışkapı Training and Research Hospital, Ankara, Turkey
| | - Ahmet Yeşilyurt
- Genetic Diagnosis Center, Ankara Dışkapı Training and Research Hospital, Ankara, Turkey
| | - Ünsal Han
- Department of Pathology & Cytology, Ankara Dışkapı Training and Research Hospital, Ankara, Turkey
| | - Tuncay Delibaşı
- Department of Endocrinology and Metabolism, Ankara Dışkapı Training and Research Hospital, Ankara, Turkey
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Pinto N, Black M, Patel K, Yoo J, Mymryk JS, Barrett JW, Nichols AC. Genomically driven precision medicine to improve outcomes in anaplastic thyroid cancer. JOURNAL OF ONCOLOGY 2014; 2014:936285. [PMID: 25276134 PMCID: PMC4170827 DOI: 10.1155/2014/936285] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 08/22/2014] [Indexed: 01/31/2023]
Abstract
Thyroid cancer is an endocrine malignancy with an incidence rate that has been increasing steadily over the past 30 years. While well-differentiated subtypes have a favorable prognosis when treated with surgical resection and radioiodine, undifferentiated subtypes, such as anaplastic thyroid cancer (ATC), are far more aggressive and have a poor prognosis. Conventional therapies (surgical resection, radiation, chemotherapy, and radioiodine) have been utilized for treatment of ATC, yet these treatments have not significantly improved the overall mortality rate. As cancer is a genetic disease, genetic alterations such as mutations, fusions, activation of oncogenes, and silencing of tumor suppressors contribute to its aggressiveness. With the use of next-generation sequencing and the Cancer Genome Atlas, mutation-directed therapy is recognized as the upcoming standard of care. In this review, we highlight the known genetic landscape of ATC and the need for a comprehensive genetic characterization of this disease in order to identify additional therapeutic targets to improve patient outcomes.
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Affiliation(s)
- Nicole Pinto
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
| | - Morgan Black
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
| | - Krupal Patel
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
| | - John Yoo
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
- London Regional Cancer Program, London, ON, Canada N6C 2R6
- Department of Oncology, The University of Western Ontario, London, ON, Canada N6A 3K7
| | - Joe S. Mymryk
- London Regional Cancer Program, London, ON, Canada N6C 2R6
- Department of Oncology, The University of Western Ontario, London, ON, Canada N6A 3K7
- Lawson Health Research Institute, London, ON, Canada N6C 2R5
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada N6A 3K7
| | - John W. Barrett
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
- London Regional Cancer Program, London, ON, Canada N6C 2R6
- Department of Oncology, The University of Western Ontario, London, ON, Canada N6A 3K7
- Lawson Health Research Institute, London, ON, Canada N6C 2R5
| | - Anthony C. Nichols
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON, Canada N6A 3K7
- London Regional Cancer Program, London, ON, Canada N6C 2R6
- Department of Oncology, The University of Western Ontario, London, ON, Canada N6A 3K7
- Lawson Health Research Institute, London, ON, Canada N6C 2R5
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON, Canada N6A 3K7
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Coexistence of papillary thyroid cancer with Hashimoto thyroiditis. Langenbecks Arch Surg 2012; 398:389-94. [PMID: 23099542 PMCID: PMC3597286 DOI: 10.1007/s00423-012-1021-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 10/15/2012] [Indexed: 11/25/2022]
Abstract
Aims Conflicting data have been reported with regard to Hashimoto thyroiditis (HT) and risk of malignancy. The aim of this study was to evaluate coexistence of papillary thyroid cancer (PTC) with HT. Patients and methods This is a retrospective cohort study in which HT was diagnosed in 452 (F/M ratio = 405:47, median age 53.5 ± 12.1 years) of 7,545 patients qualified for thyroidectomy throughout the years 2002 to 2010. Pathological reports were reviewed to identify prevalence of PTC in HT vs. non-HT patients. Results PTC was diagnosed in 106 of 452 (23.5 %) HT patients vs. 530 of 7,093 (7.5 %) non-HT patients (p < 0.001). Metastases to level VI lymph nodes were observed in 81 of 106 (76.4 %) patients with PTC in HT vs. 121 of 530 (22.8 %) patients with PTC in non-HT disease (p < 0.001). Conclusions HT was associated with a threefold increase of PTC prevalence as compared to other non-HT thyroid diseases, and the spread of PTC to level VI lymph nodes was four times more frequent in HT than in non-HT patients.
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Dinets A, Hulchiy M, Sofiadis A, Ghaderi M, Höög A, Larsson C, Zedenius J. Clinical, genetic, and immunohistochemical characterization of 70 Ukrainian adult cases with post-Chornobyl papillary thyroid carcinoma. Eur J Endocrinol 2012; 166:1049-60. [PMID: 22457234 PMCID: PMC3361791 DOI: 10.1530/eje-12-0144] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Increased incidence of papillary thyroid carcinoma (PTC) is observed as a consequence of radiation exposure in connection to the Chornobyl nuclear plant accident in 1986. In this study, we report a cohort of adult Ukrainian patients diagnosed with PTC from 2004 to 2008 following exposure at the age of 18 years or younger. METHODS In total, 70 patients were identified and clinically characterized. The common BRAF 1799T>A mutation was assessed by pyrosequencing, the RET/PTC1 and RET/PTC3 (NCOA4) rearrangements by RT-PCR, and the expression of Ki-67 (MIB-1 index), BCL2, cyclin A, and cyclin D1 by immunohistochemistry. RESULTS In total, 46/70 (66%) cases carried a BRAF mutation and/or a RET/PTC rearrangement. A BRAF mutation was detected in 26 tumors, RET/PTC1 in 20 cases, and RET/PTC3 in four cases. In four of these cases, BRAF mutation and RET/PTC rearrangement were coexisting. The BRAF mutation was underrepresented among PTCs with accompanying chronic lymphocytic thyroiditis (CLT) compared with PTCs without this feature (12 vs 44%). MIB-1 proliferation index determined by double staining with leukocyte common antigen was low (mean 0.8%; range 0.05-4.5%). Moreover, increased expression of cyclin A was observed in PTCs with a tumor size >2 cm compared with PTCs ≤2 cm (1.2 vs 0.6%). BCL2 and cyclin D1 showed frequent expression but without associations to clinical characteristics or amplification of the CCND1 locus. CONCLUSIONS Our results suggest that this cohort has frequent BRAF mutation, RET/PTC1 rearrangement, and low proliferation index. Furthermore, BRAF 1799T>A was underrepresented in PTCs with CLT, and cyclin A expression was associated with increased PTC tumor size.
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MESH Headings
- Adult
- Aged
- Biomarkers, Tumor/analysis
- Carcinoma, Papillary/chemistry
- Carcinoma, Papillary/epidemiology
- Carcinoma, Papillary/etiology
- Carcinoma, Papillary/genetics
- Carcinoma, Papillary/pathology
- Chernobyl Nuclear Accident
- Cohort Studies
- Cyclin A/analysis
- Cyclin D1/analysis
- Female
- Gene Rearrangement
- Humans
- Immunohistochemistry
- In Situ Hybridization, Fluorescence
- Ki-67 Antigen/analysis
- Male
- Middle Aged
- Mutation
- Neoplasms, Radiation-Induced/chemistry
- Neoplasms, Radiation-Induced/etiology
- Neoplasms, Radiation-Induced/genetics
- Nuclear Receptor Coactivators/genetics
- Patched Receptors
- Phenotype
- Proto-Oncogene Proteins B-raf/genetics
- Proto-Oncogene Proteins c-bcl-2/analysis
- Proto-Oncogene Proteins c-ret/genetics
- Real-Time Polymerase Chain Reaction
- Receptors, Cell Surface/genetics
- Sequence Analysis, DNA/methods
- Thyroid Neoplasms/chemistry
- Thyroid Neoplasms/epidemiology
- Thyroid Neoplasms/etiology
- Thyroid Neoplasms/genetics
- Thyroid Neoplasms/pathology
- USSR
- Ukraine/epidemiology
- Up-Regulation
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Affiliation(s)
- Andrii Dinets
- Department of Molecular Medicine and SurgeryKarolinska Institutet, Karolinska University Hospital, CMM, L8:01SE-17176, StockholmSweden
- Center for Molecular MedicineKarolinska University Hospital17176, StockholmSweden
- Kyiv City Teaching Endocrinological Center01034, KyivUkraine
- (Correspondence should be addressed to A Dinets at Department of Molecular Medicine and Surgery, Karolinska Institutet; ; C Larsson at Department of Molecular Medicine and Surgery, Karolinska Institutet; )
| | - Mykola Hulchiy
- Kyiv City Teaching Endocrinological Center01034, KyivUkraine
| | - Anastasios Sofiadis
- Department of Molecular Medicine and SurgeryKarolinska Institutet, Karolinska University Hospital, CMM, L8:01SE-17176, StockholmSweden
- Center for Molecular MedicineKarolinska University Hospital17176, StockholmSweden
| | - Mehran Ghaderi
- Department of Oncology-PathologyKarolinska Institutet17176, StockholmSweden
| | - Anders Höög
- Department of Oncology-PathologyKarolinska Institutet17176, StockholmSweden
- Department of Pathology-CytologyKarolinska University Hospital17176, StockholmSweden
| | - Catharina Larsson
- Department of Molecular Medicine and SurgeryKarolinska Institutet, Karolinska University Hospital, CMM, L8:01SE-17176, StockholmSweden
- Center for Molecular MedicineKarolinska University Hospital17176, StockholmSweden
- (Correspondence should be addressed to A Dinets at Department of Molecular Medicine and Surgery, Karolinska Institutet; ; C Larsson at Department of Molecular Medicine and Surgery, Karolinska Institutet; )
| | - Jan Zedenius
- Department of Molecular Medicine and SurgeryKarolinska Institutet, Karolinska University Hospital, CMM, L8:01SE-17176, StockholmSweden
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Abstract
Thyroid cancer is a common type of endocrine malignancy, and its incidence has been steadily increasing in many regions of the world. Initiation and progression of thyroid cancer involves multiple genetic and epigenetic alterations, of which mutations leading to the activation of the MAPK and PI3K-AKT signaling pathways are crucial. Common mutations found in thyroid cancer are point mutation of the BRAF and RAS genes as well as RET/PTC and PAX8/PPARγ chromosomal rearrangements. The mutational mechanisms seem to be linked to specific etiologic factors. Chromosomal rearrangements have a strong association with exposure to ionizing radiation and possibly with DNA fragility, whereas point mutations probably arise as a result of chemical mutagenesis. A potential role of dietary iodine excess in the generation of BRAF point mutations has also been proposed. Somatic mutations and other molecular alterations have been recognized as helpful diagnostic and prognostic markers for thyroid cancer and are beginning to be introduced into clinical practice, to offer a valuable tool for the management of patients with thyroid nodules.
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Affiliation(s)
- Yuri E Nikiforov
- Department of Pathology and Laboratory Medicine, University of Pittsburgh School of Medicine, PUH C-606, 200 Lothrop Street, Pittsburgh, PA 15213, USA.
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