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Araujo PPC, Marcello MA, Tincani AJ, Guilhen ACT, Morari EC, Ward LS. mRNA BRAF expression helps to identify papillary thyroid carcinomas in thyroid nodules independently of the presence of BRAFV600E mutation. Pathol Res Pract 2012; 208:489-92. [PMID: 22770943 DOI: 10.1016/j.prp.2012.05.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 05/07/2012] [Accepted: 05/24/2012] [Indexed: 12/21/2022]
Abstract
Literature has consistently shown associations of BRAFV600E mutation with papillary thyroid cancer clinical features. However, the clinical utility of BRAF expression has not been clinically explored so far. We studied 67 thyroid nodules (32 benign nodules and 35 PTC cases). BRAF mRNA expression levels measured by a quantitative real-time PCR and a PCR-RFLP were used to identify BRAFV600E mutation. BRAF mRNA expression was significantly higher in malignant (198.2±373.9 AU) than in benign (4.1±6.9 AU) nodules (p<0.0001). BRAF expression identified malignancy with a sensitivity of 80.6%, specificity of 77.1%, positive predictive value of 75.8%, and negative predictive value of 81.8%. A cut-point of 4.712, identified by the ROC curve, was able to sort out malignant nodules with an accuracy of 78.8%. Although we did not find any correlation between the presence of BRAF V600E mutation and clinical or tumor features such as age (p=0.309), gender (p=0.5453), ethnicity (p=0.9820), tumor size (p=1.000), multifocality (p=0.2530) or mRNA levels (p=0.7510), the study power for BRAF expression and diagnosis (99%; FPRP=0.85) indicated that data is noteworthy despite the relative small number of patients investigated. We concluded that BRAF mRNA expression may help to identify PTC among thyroid nodules independently of the presence of BRAFV600E mutation.
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Guerra A, Fugazzola L, Marotta V, Cirillo M, Rossi S, Cirello V, Forno I, Moccia T, Budillon A, Vitale M. A high percentage of BRAFV600E alleles in papillary thyroid carcinoma predicts a poorer outcome. J Clin Endocrinol Metab 2012; 97:2333-40. [PMID: 22508706 DOI: 10.1210/jc.2011-3106] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT BRAF(V600E) is considered a negative prognostic marker in papillary thyroid carcinoma (PTC), but unexplained conflicting results are present in the literature. In light of the new finding that most PTC consist of a mixture of tumor cells with wild-type and mutant BRAF, we examined the associations between the percentage of BRAF(V600E) alleles and both the clinicopathological parameters at time of diagnosis and the disease outcome in a large series of PTCs. STUDY DESIGN Tumors from 168 patients with PTC were genotyped for BRAF(V600E) using BigDye Terminator sequencing and pyrosequencing, and the clinical parameters were analyzed. The associations between clinicopathological characteristics, including disease recurrence at follow-up (median 5.1 yr) and the percentage of mutant BRAF alleles were assessed. RESULTS The observed prevalence of BRAF(V600E) was higher when using pyrosequencing then when using BigDye Terminator sequencing (53.6 vs. 36.9%). In the PTC positive for BRAF(V600E), the percentage of mutant alleles ranged from 5.1 to 44.7% of the total BRAF alleles, with a median of 20.6%. The presence or the percentage of BRAF(V600E) alleles did not correlate significantly with sex, multicentricity, lymph node metastasis, or tumor stage. The percentage of BRAF(V600E) alleles directly correlated with age at diagnosis and tumor volume (R(2) = 0.223, P = 0.039, and R(2) = 0.166, P < 0.001, respectively). The percentage of BRAF(V600E) alleles (P = 0.014), tumor volume (P = 0.012), and lymph node metastasis (P = 0.008) predicted the disease outcome. The odds ratio of recurrence for PTC with BRAF(V600E) alleles of 30% or greater, compared with that for PTC with BRAF(V600E) alleles of less than 30%, was 5.31 (P = 0.002). CONCLUSIONS A high percentage of BRAF(V600E) alleles defines a PTC molecular subtype and predicts a poorer disease outcome. The analysis of BRAF mutations by pyrosequencing is useful to refine the risk stratification of patients with PTC.
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Affiliation(s)
- Anna Guerra
- Department of Medicine and Surgery, University of Salerno, Via Allende 84081, Baronissi, Salerno, Italy
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Ricarte-Filho J, Ganly I, Rivera M, Katabi N, Fu W, Shaha A, Tuttle RM, Fagin JA, Ghossein R. Papillary thyroid carcinomas with cervical lymph node metastases can be stratified into clinically relevant prognostic categories using oncogenic BRAF, the number of nodal metastases, and extra-nodal extension. Thyroid 2012; 22:575-84. [PMID: 22471242 PMCID: PMC5206680 DOI: 10.1089/thy.2011.0431] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Papillary thyroid carcinoma (PTC) patients presenting with cervical lymph nodes (LN) metastases (M) have a variable outcome. The objective of this study is to assess the value of meticulous histopathologic examination and genotyping in stratifying these patients into clinically relevant prognostic subgroups. METHODS This was a retrospective clinical and histopathological review of PTC patients with lymph node metastases at presentation identified between 1980 and 2002 in a single institution. Primary tumors from patients who later recurred were matched to a group of patients who did not recur and subjected to mass spectrometry genotyping encompassing the most significant oncogenes in thyroid carcinomas. RESULTS There were 246 patients who satisfied the inclusion criteria. The median follow-up was 10.8 years. The presence of >3 metastatic nodes was an independent predictor of decreased recurrence free survival (p=0.03). In patients <45 years, none of 45 with 1-2 metastatic LN recurred, including 26 patients followed for a median of 13 years without radioactive iodine (RAI) therapy. BRAF mutations were found in 28 (78%) of 36 genotyped tumors. Combined positivity for BRAF and extra-nodal extension was much stronger in predicting disease specific survival (DSS) (p=0.004) than the single analysis of BRAF (p=0.12) or extra-nodal extension (p=0.02). CONCLUSIONS (i) The number of metastatic LN is an independent predictor of recurrence in all age groups and identifies a subset of young patients with excellent prognosis who may not benefit from RAI therapy. (ii) Combined positivity for BRAF and extra-nodal extension has additive prognostic value in predicting DSS. (iii) Classification systems that assign the same magnitude of risk for recurrence or death to all patients with N1 disease should be revisited.
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Affiliation(s)
- Julio Ricarte-Filho
- Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ian Ganly
- Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Michael Rivera
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Nora Katabi
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Weimin Fu
- Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ashok Shaha
- Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - R. Michael Tuttle
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - James A. Fagin
- Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ronald Ghossein
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York
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54
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Matsuse M, Sasaki K, Nishihara E, Minami S, Hayashida C, Kondo H, Suzuki K, Saenko V, Yoshiura KI, Mitsutake N, Yamashita S. Copy number alteration and uniparental disomy analysis categorizes Japanese papillary thyroid carcinomas into distinct groups. PLoS One 2012; 7:e36063. [PMID: 22558328 PMCID: PMC3340412 DOI: 10.1371/journal.pone.0036063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Accepted: 03/30/2012] [Indexed: 02/03/2023] Open
Abstract
The aim of the present study was to investigate chromosomal aberrations in sporadic Japanese papillary thyroid carcinomas (PTCs), concomitant with the analysis of oncogene mutational status. Twenty-five PTCs (11 with BRAF(V600E), 4 with RET/PTC1, and 10 without mutation in HRAS, KRAS, NRAS, BRAF, RET/PTC1, or RET/PTC3) were analyzed using Genome-Wide Human SNP Array 6.0 which allows us to detect copy number alteration (CNA) and uniparental disomy (UPD), also referred to as copy neutral loss of heterozygosity, in a single experiment. The Japanese PTCs showed relatively stable karyotypes. Seven cases (28%) showed CNA(s), and 6 (24%) showed UPD(s). Interestingly, CNA and UPD were rarely overlapped in the same tumor; the only one advanced case showed both CNA and UPD with a highly complex karyotype. Thirteen (52%) showed neither CNA nor UPD. Regarding CNA, deletions tended to be more frequent than amplifications. The most frequent and recurrent region was the deletion in chromosome 22; however, it was found in only 4 cases (16%). The degree of genomic instability did not depend on the oncogene status. However, in oncogene-positive cases (BRAF(V600E) and RET/PTC1), tumors with CNA/UPD were less frequent (5/15, 33%), whereas tumors with CNA/UPD were more frequent in oncogene-negative cases (7/10, 70%), suggesting that chromosomal aberrations may play a role in the development of PTC, especially in oncogene-negative tumors. These data suggest that Japanese PTCs may be classified into three distinct groups: CNA(+), UPD(+), and no chromosomal aberrations. BRAF(V600E) mutational status did not correlate with any parameters of chromosomal defects.
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Affiliation(s)
- Michiko Matsuse
- Department of Radiation Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Kensaku Sasaki
- Department of Human Genetics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Eijun Nishihara
- Department of Internal Medicine, Kuma Hospital, Kobe, Hyogo, Japan
| | - Shigeki Minami
- Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Chisa Hayashida
- Department of Human Genetics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Hisayoshi Kondo
- Division of Scientific Data Registry, Atomic Bomb Disease Institute, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Keiji Suzuki
- Department of Radiation Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Vladimir Saenko
- Department of Health Risk Control, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Koh-ichiro Yoshiura
- Department of Human Genetics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
| | - Norisato Mitsutake
- Department of Radiation Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
- Nagasaki University Research Centre for Genomic Instability and Carcinogenesis (NRGIC), Nagasaki, Nagasaki, Japan
| | - Shunichi Yamashita
- Department of Radiation Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
- Department of Health Risk Control, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki, Japan
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TGF-beta/Smad pathway and BRAF mutation play different roles in circumscribed and infiltrative papillary thyroid carcinoma. Virchows Arch 2012; 460:587-600. [DOI: 10.1007/s00428-012-1234-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 03/13/2012] [Accepted: 03/26/2012] [Indexed: 10/28/2022]
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Finkelstein A, Levy GH, Hui P, Prasad A, Virk R, Chhieng DC, Carling T, Roman SA, Sosa JA, Udelsman R, Theoharis CG, Prasad ML. Papillary thyroid carcinomas with and without BRAF V600E mutations are morphologically distinct. Histopathology 2012; 60:1052-9. [PMID: 22335197 DOI: 10.1111/j.1365-2559.2011.04149.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
AIMS The BRAF V600E mutation resulting in the production of an abnormal BRAF protein has emerged as the most frequent genetic alteration in papillary thyroid carcinomas (PTCs). This study was aimed at identifying distinctive features in tumours with and without the mutation. METHODS AND RESULTS Thirty-four mutation-positive and 22 mutation-negative tumours were identified by single-strand conformation polymorphism of the amplified BRAF V600E region in the tumour DNA. Mutation-positive tumours were more common in patients older than 45 years (24/33, P = 0.05), in classic (23/30, P = 0.01), tall cell (4/5) and oncocytic/Warthin-like (2/2) variants of PTC, and in subcapsular sclerosing microcarcinomas (4/4). In contrast, all 12 follicular variants (P < 0.0001) and two diffuse sclerosing variants were negative for the mutation. Mutation-positive tumours displayed infiltrative growth (32/34, P = 0.02), stromal fibrosis (33/34, P < 0.001), psammoma bodies (17/34, P = 0.05), plump eosinophilic tumour cells (22/34, P = 0.01), and classic fully developed nuclear features of PTC (33/34, P = 0.0001). Encapsulation was significantly associated with mutation-negative tumours (15/22, P = 0.02). CONCLUSIONS BRAF V600E mutation-positive and negative PTCs are morphologically different. Recognition of their morphology may help in the selection of appropriate tumours for genetic testing.
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Affiliation(s)
- Alexander Finkelstein
- Department of Pathology, Yale School of Medicine, 310 Cedar Street, New Haven, CT06520, USA
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De Falco V, Tamburrino A, Ventre S, Castellone MD, Malek M, Manié SN, Santoro M. CD44 proteolysis increases CREB phosphorylation and sustains proliferation of thyroid cancer cells. Cancer Res 2012; 72:1449-58. [PMID: 22271686 DOI: 10.1158/0008-5472.can-11-3320] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
CD44 is a marker of cancer stem-like cells and epithelial-mesenchymal transition that is overexpressed in many cancer types, including thyroid carcinoma. At extracellular and intramembranous domains, CD44 undergoes sequential metalloprotease- and γ-secretase-mediated proteolytic cleavage, releasing the intracellular protein fragment CD44-ICD, which translocates to the nucleus and activates gene transcription. Here, we show that CD44-ICD binds to the transcription factor CREB, increasing S133 phosphorylation and CREB-mediated gene transcription. CD44-ICD enhanced CREB recruitment to the cyclin D1 promoter, promoting cyclin D1 transcription and cell proliferation. Thyroid carcinoma cells harboring activated RET/PTC, RAS, or BRAF oncogenes exhibited CD44 cleavage and CD44-ICD accumulation. Chemical blockade of RET/PTC, BRAF, metalloprotease, or γ-secretase were each sufficient to blunt CD44 processing. Furthermore, thyroid cancer cell proliferation was obstructed by RNA interference-mediated knockdown of CD44 or inhibition of γ-secretase and adoptive CD44-ICD overexpression rescued cell proliferation. Together, these findings reveal a CD44-CREB signaling pathway that is needed to sustain cancer cell proliferation, potentially offering new molecular targets for therapeutic intervention in thyroid carcinoma.
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Affiliation(s)
- Valentina De Falco
- Dipartimento di Biologia e Patologia Cellulare e Molecolare, L. Califano, Università di Napoli Federico II c/o Istituto di Endocrinologia e Oncologia Sperimentale del CNR, Napoli, Italy
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58
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Menicali E, Moretti S, Voce P, Romagnoli S, Avenia N, Puxeddu E. Intracellular signal transduction and modification of the tumor microenvironment induced by RET/PTCs in papillary thyroid carcinoma. Front Endocrinol (Lausanne) 2012; 3:67. [PMID: 22661970 PMCID: PMC3357465 DOI: 10.3389/fendo.2012.00067] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2012] [Accepted: 04/30/2012] [Indexed: 01/06/2023] Open
Abstract
RET gene rearrangements (RET/PTCs) represent together with BRAF point mutations the two major groups of mutations involved in papillary thyroid carcinoma (PTC) initiation and progression. In this review, we will examine the mechanisms involved in RET/PTC-induced thyroid cell transformation. In detail, we will summarize the data on the molecular mechanisms involved in RET/PTC formation and in its function as a dominant oncogene, on the activated signal transduction pathways and on the induced gene expression modifications. Moreover, we will report on the effects of RET/PTCs on the tumor microenvironment. Finally, a short review of the literature on RET/PTC prognostic significance will be presented.
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Affiliation(s)
- Elisa Menicali
- Dipartimento di Medicina, University of PerugiaPerugia, Italy
- Centro di Proteomica e Genomica della Tiroide, University of PerugiaPerugia and Terni, Italy
| | - Sonia Moretti
- Dipartimento di Medicina, University of PerugiaPerugia, Italy
- Centro di Proteomica e Genomica della Tiroide, University of PerugiaPerugia and Terni, Italy
| | - Pasquale Voce
- Dipartimento di Medicina, University of PerugiaPerugia, Italy
- Centro di Proteomica e Genomica della Tiroide, University of PerugiaPerugia and Terni, Italy
| | | | - Nicola Avenia
- Centro di Proteomica e Genomica della Tiroide, University of PerugiaPerugia and Terni, Italy
- Dipartimento di Chirurgia, University of PerugiaPerugia, Italy
| | - Efisio Puxeddu
- Dipartimento di Medicina, University of PerugiaPerugia, Italy
- Centro di Proteomica e Genomica della Tiroide, University of PerugiaPerugia and Terni, Italy
- *Correspondence: Efisio Puxeddu, Dipartimento di Medicina, Sezione MIENDO, Via Enrico dal Pozzo – Padiglione X, 06126 Perugia, Italy. e-mail:
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59
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Targeting oncogenic serine/threonine-protein kinase BRAF in cancer cells inhibits angiogenesis and abrogates hypoxia. Proc Natl Acad Sci U S A 2011; 109:E353-9. [PMID: 22203991 DOI: 10.1073/pnas.1105026109] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Carcinomas are comprised of transformed epithelial cells that are supported in their growth by a dedicated neovasculature. How the genetic milieu of the epithelial compartment influences tumor angiogenesis is largely unexplored. Drugs targeted to mutant cancer genes may act not only on tumor cells but also, directly or indirectly, on the surrounding stroma. We investigated the role of the BRAF(V600E) oncogene in tumor/vessel crosstalk and analyzed the effect of the BRAF inhibitor PLX4720 on tumor angiogenesis. Knock-in of the BRAF(V600E) allele into the genome of human epithelial cells triggered their angiogenic response. In cancer cells harboring oncogenic BRAF, the inhibitor PLX4720 switches off the ERK pathway and inhibits the expression of proangiogenic molecules. In tumor xenografts harboring the BRAF(V600E), PLX4720 extensively modifies the vascular network causing abrogation of hypoxia. Overall, our results provide a functional link between oncogenic BRAF and angiogenesis. Furthermore, they indicate how the tumor vasculature can be "indirectly" besieged through targeting of a genetic lesion to which the cancer cells are addicted.
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60
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Wixted JHF, Rothstein JL, Eisenlohr LC. Identification of functionally distinct TRAF proinflammatory and phosphatidylinositol 3-kinase/mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (PI3K/MEK) transforming activities emanating from RET/PTC fusion oncoprotein. J Biol Chem 2011; 287:3691-703. [PMID: 22158616 DOI: 10.1074/jbc.m111.322677] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Thyroid carcinomas that harbor RET/PTC oncogenes are well differentiated, relatively benign neoplasms compared with those expressing oncogenic RAS or BRAF mutations despite signaling through shared transforming pathways. A distinction, however, is that RET/PTCs induce immunostimulatory programs, suggesting that, in the case of this tumor type, the additional pro-inflammatory pathway reduces aggressiveness. Here, we demonstrate that pro-inflammatory programs are selectively activated by TRAF2 and TRAF6 association with RET/PTC oncoproteins. Eliminating this mechanism reduces pro-inflammatory cytokine production without decreasing transformation efficiency. Conversely, ablating MEK/ERK or PI3K/AKT signaling eliminates transformation but not pro-inflammatory cytokine secretion. Functional uncoupling of the two pathways demonstrates that intrinsic pro-inflammatory pathways are not required for cellular transformation and suggests a need for further investigation into the role inflammation plays in thyroid tumor progression.
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Affiliation(s)
- Josephine H F Wixted
- Immunology and Microbial Pathogenesis Program, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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61
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Bommarito A, Richiusa P, Carissimi E, Pizzolanti G, Rodolico V, Zito G, Criscimanna A, Di Blasi F, Pitrone M, Zerilli M, Amato MC, Spinelli G, Carina V, Modica G, Latteri MA, Galluzzo A, Giordano C. BRAFV600E mutation, TIMP-1 upregulation, and NF-κB activation: closing the loop on the papillary thyroid cancer trilogy. Endocr Relat Cancer 2011; 18:669-85. [PMID: 21903858 DOI: 10.1530/erc-11-0076] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BRAF(V600E) is the most common mutation found in papillary thyroid carcinoma (PTC). Tissue inhibitor of metalloproteinases (TIMP-1) and nuclear factor (NF)-κB have been shown to play an important role in thyroid cancer. In particular, TIMP-1 binds its receptor CD63 on cell surface membrane and activates Akt signaling pathway, which is eventually responsible for its anti-apoptotic activity. The aim of our study was to evaluate whether interplay among these three factors exists and exerts a functional role in PTCs. To this purpose, 56 PTC specimens were analyzed for BRAF(V600E) mutation, TIMP-1 expression, and NF-κB activation. We found that BRAF(V600E) mutation occurs selectively in PTC nodules and is associated with hyperactivation of NF-κB and upregulation of both TIMP-1 and its receptor CD63. To assess the functional relationship among these factors, we first silenced BRAF gene in BCPAP cells, harboring BRAF(V600E) mutation. We found that silencing causes a marked decrease in TIMP-1 expression and NF-κB binding activity, as well as decreased invasiveness. After treatment with specific inhibitors of MAPK pathway, we found that only sorafenib was able to increase IκB-α and reduce both TIMP-1 expression and Akt phosphorylation in BCPAP cells, indicating that BRAF(V600E) activates NF-κB and this pathway is MEK-independent. Taken together, our findings demonstrate that BRAF(V600E) causes upregulation of TIMP-1 via NF-κB. TIMP-1 binds then its surface receptor CD63, leading eventually to Akt activation, which in turn confers antiapoptotic behavior and promotion of cell invasion. The recognition of this functional trilogy provides insight on how BRAF(V600E) determines cancer initiation, progression, and invasiveness in PTC, also identifying new therapeutic targets for the treatment of highly aggressive forms.
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Affiliation(s)
- Alessandra Bommarito
- Sezione di Endocrinologia, Laboratorio di Endocrinologia Molecolare, Dipartimento di Biomedico di Medicina Interna e Specialistica (DIBIMIS), University of Palermo, Italy
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Rusinek D, Szpak-Ulczok S, Jarzab B. Gene expression profile of human thyroid cancer in relation to its mutational status. J Mol Endocrinol 2011; 47:R91-103. [PMID: 21798995 DOI: 10.1530/jme-11-0023] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review describes the gene expression profile changes associated with the presence of different mutations that contribute to thyroid cell carcinogenesis. The results are discussed in the context of thyroid cancer biology and of the implications for disease prognosis, while the diagnostic aspect has been omitted. For papillary thyroid cancer (PTC), the most characteristic gene expression profile is associated with the presence of BRAF mutation. BRAF-associated PTC differ profoundly from RET/PTC or RAS-associated cancers. Simultaneously, they retain many characteristic gene expression features common for all PTCs, induced by the alternative mutations activating MAPK pathway. Although the difference between papillary and follicular thyroid cancer (FTC) is significant at the gene expression profile level, surprisingly, the RAS-related signature of FTC is not well specified. PAX8/peroxisome proliferator-activated receptor γ (PPARγ) rearrangements, which occur in FTC as an alternative to the RAS mutation, are associated with specific changes in gene expression. Furthermore, the difference between well-differentiated thyroid cancers and poorly differentiated and anaplastic thyroid cancers is mainly a reflection of tumor degree of differentiation and may not be attributed to the presence of characteristic mutations.
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Affiliation(s)
- Dagmara Rusinek
- Department of Nuclear Medicine and Endocrine Oncology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Wybrzeze Armii Krajowej 15, 44-101 Gliwice, Poland
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63
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Chakravarty D, Santos E, Ryder M, Knauf JA, Liao XH, West BL, Bollag G, Kolesnick R, Thin TH, Rosen N, Zanzonico P, Larson SM, Refetoff S, Ghossein R, Fagin JA. Small-molecule MAPK inhibitors restore radioiodine incorporation in mouse thyroid cancers with conditional BRAF activation. J Clin Invest 2011; 121:4700-11. [PMID: 22105174 DOI: 10.1172/jci46382] [Citation(s) in RCA: 268] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 10/12/2011] [Indexed: 12/15/2022] Open
Abstract
Advanced human thyroid cancers, particularly those that are refractory to treatment with radioiodine (RAI), have a high prevalence of BRAF (v-raf murine sarcoma viral oncogene homolog B1) mutations. However, the degree to which these cancers are dependent on BRAF expression is still unclear. To address this question, we generated mice expressing one of the most commonly detected BRAF mutations in human papillary thyroid carcinomas (BRAF(V600E)) in thyroid follicular cells in a doxycycline-inducible (dox-inducible) manner. Upon dox induction of BRAF(V600E), the mice developed highly penetrant and poorly differentiated thyroid tumors. Discontinuation of dox extinguished BRAF(V600E) expression and reestablished thyroid follicular architecture and normal thyroid histology. Switching on BRAF(V600E) rapidly induced hypothyroidism and virtually abolished thyroid-specific gene expression and RAI incorporation, all of which were restored to near basal levels upon discontinuation of dox. Treatment of mice with these cancers with small molecule inhibitors of either MEK or mutant BRAF reduced their proliferative index and partially restored thyroid-specific gene expression. Strikingly, treatment with the MAPK pathway inhibitors rendered the tumor cells susceptible to a therapeutic dose of RAI. Our data show that thyroid tumors carrying BRAF(V600E) mutations are exquisitely dependent on the oncoprotein for viability and that genetic or pharmacological inhibition of its expression or activity is associated with tumor regression and restoration of RAI uptake in vivo in mice. These findings have potentially significant clinical ramifications.
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Affiliation(s)
- Debyani Chakravarty
- Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
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64
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Durante C, Tallini G, Puxeddu E, Sponziello M, Moretti S, Ligorio C, Cavaliere A, Rhoden KJ, Verrienti A, Maranghi M, Giacomelli L, Russo D, Filetti S. BRAF(V600E) mutation and expression of proangiogenic molecular markers in papillary thyroid carcinomas. Eur J Endocrinol 2011; 165:455-63. [PMID: 21653734 DOI: 10.1530/eje-11-0283] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Tyrosine kinase inhibitors (TKIs) are evaluated for treatment of radioiodine refractory thyroid cancer. Their effects in this setting are based on blockade of proangiogenic signaling mediated by receptors for vascular endothelial growth factors (VEGFs) and platelet-derived growth factors (PDGF). Most TKIs also block other cancer-relevant kinases, such as B-type Raf kinase (BRAF), which are constitutively activated in approximately half of papillary thyroid carcinomas (PTCs), but the impact of these effects is not clear. DESIGN The aim of our study was to investigate the impact of BRAF(V600E) on proangiogenic gene expression and microvascular features of PTCs. METHODS mRNA levels for VEGFA, VEGF receptors, and coreceptors (VEGFRs 1, 2, and 3, neuropilin-1), and PDGF receptor β (PDGFRβ or PDGFRB) were measured with real-time PCR in BRAF(V600E) (n=55) and wild-type BRAF (BRAF-wt; n=35) PTCs. VEGF and VEGFR protein expression and microvessel densities (MVD) and lymphatic vessel densities (LVDs) were assessed by immunohistochemistry in 22 of the 90 PTCs (including 11 BRAF(V600E) cases). Angiogenic gene expression was also studied in vitro after induction/silencing of the BRAF(V600E) mutation in thyrocyte lines. RESULTS Transcript levels of proangiogenic factors were significantly lower in BRAF(V600E) PTCs versus BRAF-wt PTCs (P<0.0001), but MVD and LVDs were not significantly different. VEGFA mRNA levels in thyroid cell lines decreased when BRAF(V600E) mutation was induced (P=0.01) and increased when it was silenced (P=0.01). CONCLUSIONS Compared with BRAF-wt PTCs, those harboring BRAF(V600E) exhibit downregulated VEGFA, VEGFR, and PDGFRβ expression, suggesting that the presence of BRAF mutation does not imply a stronger prediction of response to drugs targeting VEGF and PDGFB signaling pathways.
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Affiliation(s)
- Cosimo Durante
- Dipartimento di Medicina Interna e Specialità Mediche, Università di Roma Sapienza, V.le del Policlinico, 155, 00161 Roma, Italy
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Abstract
BRAFV600E is a constitutively active onco-kinase and is the most common genetic alteration in papillary thyroid carcinoma (PTC), and in anaplastic thyroid carcinoma as well, albeit at a lower frequency. The BRAFV600E mutation in some studies has been significantly associated with extra-thyroidal extension, metastases, recurrence, and mortality in patients with PTC. A recent genome-wide expression profiling approach (Gene Set Enrichment Analysis (GSEA)) and in vitro and in vivo functional studies revealed that BRAFV600E affects extracellular matrix composition (i.e. increased expression of some collagens and laminins) and promotes thyroid cancer migration and invasion. BRAFV600E through the phospho-MEK1/2 and phospho-ERK1/2 pathway may control a network of genes crucial in integrating and regulating the extracellular and intracellular signaling in thyroid cancer cells, which may be fundamental to trigger an abnormal cell differentiation/totipotency and shape/polarity, and contribute to tumor aggressiveness mechanisms (i.e. cell adhesion, migration, and invasion). Increasing our knowledge of BRAFV600E-modulated ECM genes and targeting the subset of genes essential for tumor aggressiveness will help establish a novel paradigm for treatment of thyroid cancers harboring BRAFV600E. Furthermore, identifying downstream events from the BRAFV600E/ERK1/2 pathway will eventually identify novel biomarkers that can be used to correlate with disease outcome and overall survival.
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Smith RA, Salajegheh A, Weinstein S, Nassiri M, Lam AKY. Correlation between BRAF mutation and the clinicopathological parameters in papillary thyroid carcinoma with particular reference to follicular variant. Hum Pathol 2011; 42:500-6. [DOI: 10.1016/j.humpath.2009.09.023] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Revised: 09/18/2009] [Accepted: 09/25/2009] [Indexed: 01/19/2023]
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Nucera C, Lawler J, Parangi S. BRAF(V600E) and microenvironment in thyroid cancer: a functional link to drive cancer progression. Cancer Res 2011; 71:2417-22. [PMID: 21447745 DOI: 10.1158/0008-5472.can-10-3844] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Papillary thyroid cancer (PTC) rates continue to increase in the United States and Europe, and, although most patients do well, some recur and die of their disease. Patients with PTC harboring the BRAF(V600E) mutation seem to display a more aggressive clinical behavior, but little is known about the role of this mutation in crucial processes in the tumor microenvironment, such as tumor adhesion, migration, invasion, and metastasis. The extracellular matrix (ECM) microenvironment is not merely a structural scaffold for the cellular elements of the epithelial and stromal microenvironment, but it also elicits a profound influence on cell behavior affecting viability, proliferation, adhesion, and motility. The effects of BRAF(V600E) on cell surface receptors (i.e., integrins) and ECM noncellular components [i.e., thrombospondin-1 (TSP-1) and fibronectin (FN)] seem to trigger different pathologic biological processes in a cell context-dependent manner. This review focuses on the recent progress in understanding the role of BRAF(V600E) in the regulation of some ECM noncellular components and trans-membrane receptors of the microenvironment in PTC in order to design novel targeted therapies directed at the BRAF(V600E) multifaceted signaling cascades. Some of these targeted therapeutics, such as ATP-competitive BRAF(V600E) inhibitors (i.e., orally bioavailable PLX4720 and PLX4032 compounds), are already under investigation.
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Affiliation(s)
- Carmelo Nucera
- Thyroid Cancer Research Laboratory, Endocrine Surgery Unit, Massachusetts General Hospital, Harvard Medical School, and Division of Cancer Biology and Angiogenesis, Department of Pathology, Harvard Medical School, Boston, Massachusetts, USA
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Induction of heparanase-1 expression by mutant B-Raf kinase: role of GA binding protein in heparanase-1 promoter activation. Neoplasia 2011; 12:946-56. [PMID: 21076620 DOI: 10.1593/neo.10790] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 08/11/2010] [Accepted: 08/16/2010] [Indexed: 01/15/2023] Open
Abstract
Heparanase-1 (HPR1), an endoglycosidase that specifically degrades heparan sulfate (HS) proteoglycans, is overexpressed in a variety of malignancies. Our present study sought to determine whether oncogene BRAF and RAS mutations lead to increased HPR1 expression. Reverse transcription-polymerase chain reaction analysis revealed that HPR1 gene expression was increased in HEK293 cells transiently transfected with a mutant BRAF or RAS gene. Flow cytometric analysis revealed that B-Raf activation led to loss of the cell surface HS, which could be blocked by two HPR1 inhibitors: heparin and PI-88. Cotransfection of a BRAF or RAS mutant gene with HPR1 promoter-driven luciferase reporters increased luciferase reporter gene expression in HEK293 cells. Knockdown of BRAF expression in a BRAF-mutated KAT-10 tumor cell line led to the suppression of HPR1 gene expression, subsequently leading to increased cell surface HS levels. Truncational and mutational analyses of the HPR1 promoter revealed that the Ets-relevant elements in the HPR1 promoter were critical for BRAF activation-induced HPR1 expression. Luciferase reporter gene expression driven by a four-copy GA binding protein (GABP) binding site was significantly lower in BRAF siRNA-transfected KAT-10 cells than in the control siRNA-transfected cells. We further showed that BRAF knockdown led to suppression of the expression of the GABPβ, an Ets family transcription factor involved in regulating HPR1 promoter activity. Taken together, our study suggests that B-Raf kinase activation plays an important role in regulating HPR1 expression. Increased HPR1 expression may contribute to the aggressive behavior of BRAF-mutated cancer.
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Russo MA, Arciuch VGA, Di Cristofano A. Mouse models of follicular and papillary thyroid cancer progression. Front Endocrinol (Lausanne) 2011; 2:119. [PMID: 22654848 PMCID: PMC3356054 DOI: 10.3389/fendo.2011.00119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Accepted: 12/30/2011] [Indexed: 12/15/2022] Open
Abstract
A significant number of well-differentiated thyroid cancers progress or recur, becoming resistant to current therapeutic options. Mouse models recapitulating the genetic and histological features of advanced thyroid cancer have been an invaluable tool to dissect the mechanisms involved in the progression from indolent, well differentiated tumors to aggressive, poorly differentiated carcinomas, and to identify novel therapeutic targets. In this review, we focus on the lessons learned from models of epithelial cell-derived thyroid cancer showing progression from hyperplastic lesions to locally invasive and metastatic carcinomas.
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Affiliation(s)
- Marika A. Russo
- Department of Developmental and Molecular Biology, Albert Einstein College of MedicineBronx, NY, USA
| | - Valeria G. Antico Arciuch
- Department of Developmental and Molecular Biology, Albert Einstein College of MedicineBronx, NY, USA
| | - Antonio Di Cristofano
- Department of Developmental and Molecular Biology, Albert Einstein College of MedicineBronx, NY, USA
- *Correspondence: Antonio Di Cristofano, Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Price Center for Genetic and Translational Medicine, 1301 Morris Park Avenue, Room 302, Bronx, NY 10461, USA. e-mail:
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Nowicki TS, Zhao H, Darzynkiewicz Z, Moscatello A, Shin E, Schantz S, Tiwari RK, Geliebter J. Downregulation of uPAR inhibits migration, invasion, proliferation, FAK/PI3K/Akt signaling and induces senescence in papillary thyroid carcinoma cells. Cell Cycle 2011; 10:100-7. [PMID: 21191179 DOI: 10.4161/cc.10.1.14362] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Papillary thyroid carcinoma (PTC) is the most common endocrine and thyroid malignancy. The urokinase plasminogen activator receptor (uPAR) plays an important role in cancer pathogenesis, including breakdown of the extracellular matrix, invasion, and metastasis. Additionally, there is increasing evidence that uPAR also promotes tumorigenesis via the modulation of multiple signaling pathways. BRAFV600E, the most common initial genetic mutation in PTC, leads to ERK1/2 hyperphosphorylation, which has been shown in numerous cancers to induce uPAR. Treatment of the BRAFV600E-positive PTC cell line, BCPAP, with the MEK/ERK inhibitor U0126 reduced uPAR RNA levels by 90%. siRNA-mediated down-regulation of uPAR in BCPAP cells resulted in greatly decreased activity in the focal adhesion kinase (FAK)/phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. This phenomenon was concurrent with drastically reduced proliferation rates and decreased clonigenic survival, as well as demonstrated senescence-associated nuclear morphology and induction of b-galactosidase activity. uPAR-knockdown BCPAP cells also displayed greatly reduced migration and invasion rates, as well as a complete loss of the cells' ability to augment their invasiveness following plasminogen supplementation. Taken together, these data provide new evidence of a novel role for uPAR induction (as a consequence of constitutive ERK1/2 activation) as a central component in PTC pathogenesis, and highlight the potential of uPAR as a therapeutic target.
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Affiliation(s)
- Theodore S Nowicki
- Department of Microbiology and Immunology, New York Medical College, Valhalla, NY, USA
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71
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Nucera C, Lawler J, Hodin R, Parangi S. The BRAFV600E mutation: what is it really orchestrating in thyroid cancer? Oncotarget 2010; 1:751-756. [PMID: 21321384 PMCID: PMC3074562 DOI: 10.18632/oncotarget.210] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 12/31/2010] [Indexed: 11/25/2022] Open
Abstract
BRAFV600E is a constitutively active onco-kinase and is the most common genetic alteration in papillary thyroid carcinoma (PTC), and in anaplastic thyroid carcinoma as well, albeit at a lower frequency. The BRAFV600E mutation in some studies has been significantly associated with extra-thyroidal extension, metastases, recurrence, and mortality in patients with PTC. A recent genome-wide expression profiling approach (Gene Set Enrichment Analysis (GSEA)) and in vitro and in vivo functional studies revealed that BRAFV600E affects extracellular matrix composition (i.e. increased expression of some collagens and laminins) and promotes thyroid cancer migration and invasion. BRAFV600E through the phospho-MEK1/2 and phospho-ERK1/2 pathway may control a network of genes crucial in integrating and regulating the extracellular and intracellular signaling in thyroid cancer cells, which may be fundamental to trigger an abnormal cell differentiation/totipotency and shape/polarity, and contribute to tumor aggressiveness mechanisms (i.e. cell adhesion, migration, and invasion). Increasing our knowledge of BRAFV600E-modulated ECM genes and targeting the subset of genes essential for tumor aggressiveness will help establish a novel paradigm for treatment of thyroid cancers harboring BRAFV600E. Furthermore, identifying downstream events from the BRAFV600E/ERK1/2 pathway will eventually identify novel biomarkers that can be used to correlate with disease outcome and overall survival.
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Affiliation(s)
- Carmelo Nucera
- Thyroid Cancer Research Laboratory, Endocrine Surgery Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Division of Cancer Biology and Angiogenesis, Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Jack Lawler
- Division of Cancer Biology and Angiogenesis, Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Richard Hodin
- Thyroid Cancer Research Laboratory, Endocrine Surgery Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Sareh Parangi
- Thyroid Cancer Research Laboratory, Endocrine Surgery Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Rivera M, Ricarte-Filho J, Tuttle RM, Ganly I, Shaha A, Knauf J, Fagin J, Ghossein R. Molecular, morphologic, and outcome analysis of thyroid carcinomas according to degree of extrathyroid extension. Thyroid 2010; 20:1085-93. [PMID: 20860430 PMCID: PMC4984786 DOI: 10.1089/thy.2010.0174] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND The impact of varying degrees of extrathyroid extension (ETE), especially microscopic ETE (METE), on survival in thyroid carcinomas (TC) has not been well established. Our objective was to analyze ETE at the molecular and histologic levels and assess the effect of its extent on outcome. METHODS All cases of TC with ETE but without nodal metastases at presentation (NMP) were identified over a 20-year period and grouped into gross and METE. Twelve papillary thyroid carcinomas (PTCs) without ETE and NMP were also analyzed. Cases with paraffin tissues were subjected to mass spectrometry genotyping encompassing the most significant oncogenes in TC: 111 mutations in RET, BRAF, NRAS, HRAS, KRAS, PIK3CA, and AKT1, and other related genes were surveyed. RESULTS Eighty-one (10%) of 829 patients in the database had ETE and no NMP. There was a much higher frequency of poorly differentiated and anaplastic carcinomas (12/29, 41%) in patients with gross ETE than in those with METE (3/52, 6%) (p < 0.01). There was a higher disease-specific survival (DSS) in patients with METE than in those with gross ETE (p < 0.0001). Except for an anaplastic case, no recurrences were detected in 45 patients with METE, including 23 PTC patients followed up for a median of 10 years without radioactive iodine therapy. Within patients with gross invasion into trachea/esophagus, tumors with high mitotic activity and/or tumor necrosis correlated with worse DSS (p < 0.05). Fifty-six cases with ETE were genotyped as follows: BRAFV600E, 39 (70%); BRAFV600E-AKT1, 1 (1.8%); NRAS, 1 (1.8%); KRAS, 1 (1.8%); RET/PTC, 3 (5%); wild type, 11 (19.6%). Within PTCs, BRAF positivity rate increased the risk of ETE (p = 0.01). If PTC follicular variants are excluded, BRAF positivity does not correlate with ETE status within classical/tall cell PTC. CONCLUSION (i) PTCs with METE without NMP have an extremely low recurrence rate in contrast to tumors with gross ETE. (ii) High mitotic activity and/or tumor necrosis confers worse DSS even in patients stratified for gross ETE in trachea/esophagus. (iii) BRAF positivity correlates with the presence of ETE in PTC, but this relationship is lost within classical/tall cell PTC if follicular variants are excluded from the analysis.
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Affiliation(s)
- Michael Rivera
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Julio Ricarte-Filho
- Department of Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | | | - Ian Ganly
- Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ashok Shaha
- Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Jeffrey Knauf
- Department of Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - James Fagin
- Department of Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ronald Ghossein
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York
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74
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Cho NL, Lin CI, Whang EE, Carothers AM, Moore FD, Ruan DT. Sulindac reverses aberrant expression and localization of beta-catenin in papillary thyroid cancer cells with the BRAFV600E mutation. Thyroid 2010; 20:615-22. [PMID: 20470206 DOI: 10.1089/thy.2009.0415] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Activation of the Wnt/beta-catenin signaling pathway is implicated in thyroid tumorigenesis, and up to 90% of papillary thyroid cancer (PTC) demonstrate aberrant expression of beta-catenin. Nonsteroidal antiinflammatory drugs reverse aberrant beta-catenin expression and localization in colon cancer. In this study, we tested the hypothesis that the nonsteroidal antiinflammatory drug sulindac would reverse aberrant beta-catenin activity in thyroid cancer cells. METHODS beta-catenin protein levels were determined in thyroidectomy specimens from six consecutive patients and in three different thyroid cancer cells lines (8505-C, KTC-1, and TPC-1) by immunoblotting. Cells of 8505-C and KTC-1 harbor the BRAF(V600E) mutation, and TPC-1 has the RET/PTC rearrangement. All cell lines were treated with sulindac (100 microM for up to 72 hours). Protein levels of c-myc and cyclin D1 were detected by immunoblotting, and beta-catenin localization was determined by immunocytochemistry in the PTC cell lines. PCCL3 rat thyroid cells that conditionally overexpress either BRAF(V600E) or RET/PTC were also treated with sulindac. RESULTS All PTC specimens and cell lines expressed high levels of beta-catenin protein and displayed aberrant nuclear and cytoplasmic localization of beta-catenin. Exposure to sulindac for 48 hours reduced beta-catenin expression in 8505-C and KTC-1 cells, but not in TPC-1 cells. Further, sulindac treatment reduced c-myc and cyclin D1 levels in 8505-C and KTC-1 cells, but had no effect in TPC-1 cells. Immunocytochemistry demonstrated that sulindac treatment redistributed beta-catenin from the nucleus to the membrane in 8505-C and KTC-1 cells. However, sulindac did not affect beta-catenin localization in TPC-1 cells. Finally, sulindac was effective in decreasing beta-catenin expression and cellular proliferation in BRAF(V600E)-overexpressing cells, but not in RET/PTC3-overexpressing cells. CONCLUSIONS Taken together, our findings demonstrate that sulindac treatment reverses beta-catenin activity in 8505-C and KTC-1 cell lines with the BRAF(V600E), but not in TPC-1 cells with the RET/PTC mutation. Future studies should investigate the potential for beta-catenin-directed therapy for patients with advanced thyroid cancers.
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Affiliation(s)
- Nancy L Cho
- Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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75
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Roger PP, van Staveren WCG, Coulonval K, Dumont JE, Maenhaut C. Signal transduction in the human thyrocyte and its perversion in thyroid tumors. Mol Cell Endocrinol 2010; 321:3-19. [PMID: 19962425 DOI: 10.1016/j.mce.2009.11.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 11/23/2009] [Accepted: 11/27/2009] [Indexed: 11/19/2022]
Abstract
The study of normal signal transduction pathways regulating the proliferation and differentiation of a cell type allows to predict and to understand the perversions of these pathways which lead to tumorigenesis. In the case of the human thyroid cell, three cascades are mostly involved in tumorigenesis: The pathways and genetic events affecting them are described. Caveats in the use of models and the interpretation of results are formulated and the still pending questions are outlined.
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Affiliation(s)
- Pierre P Roger
- I.R.I.B.H.M., Université Libre de Bruxelles, Campus Erasme, Route de Lennik 808, B - 1070 Bruxelles, Belgium
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76
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Xing M. Prognostic utility of BRAF mutation in papillary thyroid cancer. Mol Cell Endocrinol 2010; 321:86-93. [PMID: 19883729 PMCID: PMC2849928 DOI: 10.1016/j.mce.2009.10.012] [Citation(s) in RCA: 148] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 09/18/2009] [Accepted: 10/21/2009] [Indexed: 11/29/2022]
Abstract
Papillary thyroid cancer (PTC) is a common endocrine malignancy that frequently harbors the oncogenic T1799A BRAF mutation. As a novel prognostic molecular marker, this mutation has received considerable attention in recent years for its potential utility in the risk stratification and management of PTC. In PTC, BRAF mutation is closely associated with extrathyroidal extension, lymph node metastasis, advanced tumor stages, disease recurrence, and even patient mortality. Many of the responsible molecular derangements promoted by, or associated with, BRAF mutation have been identified, including over-expression of tumor-promoting genes, suppression of tumor-suppressor genes, and silencing of thyroid iodide-handling genes, resulting in impairment or loss of radioiodine avidity and hence the failure of radioiodine treatment of PTC. BRAF mutation can be readily tested on thyroid fine needle aspiration biopsy specimens, with high preoperative predictive probabilities for clinicopathological outcomes of PTC. As such, the knowledge of BRAF mutation status can facilitate more accurate risk stratification and better decision making at various steps in the management of PTC, from preoperative planning of initial surgical scale to postoperative decisions about appropriate radioiodine treatment and thyroid-stimulating hormone suppression, and to selections of appropriate surveillance modalities for PTC recurrence. The greatest utility of BRAF mutation status is in those cases where traditional clinicopathological criteria alone would otherwise be unreliable in the risk stratification and management of PTC. Use of this unique molecular marker, in conjunction with conventional clinicopathological risk factors, to assist the prognostication of PTC is likely to improve the efficiency of contemporary management of thyroid cancer.
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Affiliation(s)
- Mingzhao Xing
- Division of Endocrinology and Metabolism, The Johns Hopkins University School of Medicine, 1830 East Monument Street, Suite 333, Baltimore, MD 21287, United States.
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Teimoori-Toolabi L, Azadmanesh K, Amanzadeh A, Zeinali S. Selective suicide gene therapy of colon cancer exploiting the urokinase plasminogen activator receptor promoter. BioDrugs 2010; 24:131-46. [PMID: 20199127 DOI: 10.2165/11530840-000000000-00000] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Colon cancer is the third and fourth most prevalent cancer among Iranian men and women, respectively. Suicide gene therapy is one of the alternative therapeutic modalities for cancer. The application of specific promoters for therapeutic genes should decrease the adverse effects of this modality. The combined aims of this study were to design a specific suicide gene therapy construct for colon cancer and study its effect in distinct representatives of transformed and nontransformed cells. The KRAS oncogene signaling pathway is one of the most important signaling pathways activated in colon cancer; therefore, we inserted the urokinase plasminogen activator receptor (uPAR; PLAUR gene) promoter as one of the upregulated promoters by this pathway upstream of a suicide gene (thymidine kinase [TK]) and a reporter gene (beta-galactosidase, beta-gal [LacZ]). This promoter is a natural combination of different motifs responsive to the RAS signaling pathway, such as the transcription factors AP1 (FOS/JUN), SP1, SP3, and AP2alpha, and nuclear factor kappa B (NFkappaB). The reporter plasmid under the control of the uPAR promoter (PUCUPARLacZ) had the ability to express beta-gal in colon cancer cells (human colon adenocarcinoma [SW480] and human colorectal carcinoma [HCT116] cell lines), while it could not express beta-gal in nontransformed human umbilical vein endothelial cells (HUVEC) and normal colon cells. After confirming the ability of pUCUPARTK (suicide plasmid) to express TK in SW480 and HCT116 cells by real-time PCR, cytotoxicity assays showed that pUCUPARTK decreased the viability of these cells in the presence of ganciclovir 20 and 40 microg/mL (and higher), respectively. Although M30 CytoDEATH antibody could not detect a significant rate of apoptosis induced by ganciclovir in pUCUPARTK-transfected HCT116 cells, the percentage of stained cells was marked in comparison with untreated cells. While this antibody could detect apoptosis in HCT116 cell line transfected with positive control plasmid, it could not detect apoptosis in SW480 cells transfected with the same positive control. This discrepancy could be attributed to the different mechanisms of TK/ganciclovir-induced apoptosis in tumor protein p53 (TP53)-expressing (HCT116) and -deficient (SW480) cells. Annexin-propidium iodide staining could detect apoptosis in treated, pUCUPARTK-transfected SW480 and HCT116 cells. This study showed that the uPAR promoter can be considered as a suitable candidate for specific suicide gene therapy of colon cancer and probably other cancers in which the RAS signaling pathway is involved in their carcinogenesis process.
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Affiliation(s)
- Ladan Teimoori-Toolabi
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
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Role of matrix metalloproteinases in recurrent corneal melting. Exp Eye Res 2010; 90:583-90. [DOI: 10.1016/j.exer.2010.02.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 02/02/2010] [Accepted: 02/04/2010] [Indexed: 02/06/2023]
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79
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Tang KT, Lee CH. BRAF mutation in papillary thyroid carcinoma: pathogenic role and clinical implications. J Chin Med Assoc 2010; 73:113-28. [PMID: 20230995 DOI: 10.1016/s1726-4901(10)70025-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 12/11/2009] [Indexed: 12/30/2022] Open
Abstract
Papillary thyroid cancer (PTC) is the most common endocrine malignancy, accounting for 85-90% of all thyroid cancers. Genetic alternations involving the mitogen-activated protein kinase (MAPK) pathway are frequently demonstrated in PTC, such as RET/PTC, RAS, and B-type Raf kinase (BRAF) mutations. Over 90% of BRAF mutations are T1799A, resulting in a BRAF(V600E) mutation. BRAF(V600E) is present in approximately 50% of PTC and also found in aggressive histologic variants and PTC-derived anaplastic thyroid cancer, but is rare in follicular variants, and not found in follicular thyroid cancer. The tumorigenic role of BRAF(V600E) in the development of PTC was documented in thyroid-targeted BRAF(V600E) transgenic mice, and rat thyroid cells overexpressed with BRAF(V600E) suggested that BRAF(V600E) is an initiator of tumorigenesis and is required for tumor progression in PTC. Most clinical studies have demonstrated an association of BRAF(V600E) mutation with aggressive clinicopathologic characteristics and high tumor recurrence, although the results are controversial. The association is also observed in patients with papillary thyroid microcarcinomas and low-risk PTC. As a highly specific and unique mutation in PTC, testing for BRAF(V600E) in fine-needle aspiration specimens has been shown to refine the diagnostic accuracy of PTC in indeterminate cytology. Preoperative BRAF(V600E) analysis in low-risk patients may provide important value for prognostication, and these patients might benefit from receiving more intensive management and frequent follow-up. BRAF-targeted therapies have been developed to treat various human cancers including advanced thyroid cancers. Preclinical results are encouraging, but the anticancer effects of clinical trials are disappointing. Studies of multi-kinase inhibitors and/or combination with other regimens are underway in the treatment of advanced thyroid cancers. In this article, we review the pathogenesis of PTC, and the clinical implications of BRAF(V600E) mutation in the diagnosis, prognosis and potential targeted therapeutic strategies for thyroid cancers.
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Affiliation(s)
- Kam-Tsun Tang
- Department of Medical Education and Research, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C
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80
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Zuo H, Gandhi M, Edreira MM, Hochbaum D, Nimgaonkar VL, Zhang P, Dipaola J, Evdokimova V, Altschuler DL, Nikiforov YE. Downregulation of Rap1GAP through epigenetic silencing and loss of heterozygosity promotes invasion and progression of thyroid tumors. Cancer Res 2010; 70:1389-97. [PMID: 20124489 DOI: 10.1158/0008-5472.can-09-2812] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Thyroid cancer is the most common type of endocrine malignancy, encompassing tumors with various levels of invasive growth and aggressiveness. Rap1GAP, a Rap1 GTPase-activating protein, inhibits the RAS superfamily protein Rap1 by facilitating hydrolysis of GTP to GDP. In this study, we analyzed 197 thyroid tumor samples and showed that Rap1GAP was frequently lost or downregulated in various types of tumors, particularly in the most invasive and aggressive forms of thyroid cancer. The downregulation was due to promoter hypermethylation and/or loss of heterozygosity, found in the majority of thyroid tumors. Treatment with demethylating agent 5-aza-deoxycytidine and/or histone deacetylation inhibitor trichostatin A induced gene reexpression in thyroid cells. A genetic polymorphism, Y609C, was seen in 7% of thyroid tumors but was not related to gene downregulation. Loss of Rap1GAP expression correlated with tumor invasiveness but not with specific mutations activating the mitogen-activated protein kinase pathway. Rap1GAP downregulation was required in vitro for cell migration and Matrigel invasion. Recovery of Rap1GAP expression inhibited thyroid cell proliferation and colony formation. Overall, our findings indicate that epigenetic or genetic loss of Rap1GAP is very common in thyroid cancer, where these events are sufficient to promote cell proliferation and invasion.
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Affiliation(s)
- Hui Zuo
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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81
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Riesco-Eizaguirre G, Rodríguez I, De la Vieja A, Costamagna E, Carrasco N, Nistal M, Santisteban P. The BRAFV600E oncogene induces transforming growth factor beta secretion leading to sodium iodide symporter repression and increased malignancy in thyroid cancer. Cancer Res 2009; 69:8317-25. [PMID: 19861538 DOI: 10.1158/0008-5472.can-09-1248] [Citation(s) in RCA: 202] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The activating mutation BRAF(V600E) is a frequent genetic event in papillary thyroid carcinomas (PTC) that predicts a poor prognosis, leading to loss of sodium/iodide symporter (NIS) expression and subsequent radioiodide-refractory metastatic disease. The molecular basis of such an aggressive behavior induced by BRAF remains unclear. Here, we show a mechanism through which BRAF induces NIS repression and promotes epithelial to mesenchimal transition and invasion based on the operation of an autocrine transforming growth factor (TGF)beta loop. BRAF induces secretion of functional TGFbeta and blocking TGFbeta/Smad signaling at multiple levels rescues BRAF-induced NIS repression. Although this mechanism is MAP/extracellular signal-regulated kinase (ERK) kinase (MEK)-ERK independent, secreted TGFbeta cooperates with MEK-ERK signaling in BRAF-induced cell migration, Matrigel invasion, and EMT. Consistent with this process, TGFbeta and other key components of TGFbeta signaling, such as TbetaRII and pSmad2, are overexpressed in human PTC, suggesting a widespread activation of this pathway by locally released TGFbeta. Moreover, this high TGFbeta/Smad activity is associated with PTC invasion, nodal metastasis, and BRAF status. Interestingly, TGFbeta is overexpressed in the invasive front, whereas NIS is preferentially expressed in the central regions of the tumors, suggesting that this negative correlation between TGFbeta and NIS occurs locally inside the tumor. Our study describes a novel mechanism of NIS repression in thyroid cancer and provides evidence that TGFbeta may play a key role in promoting radioiodide resistance and tumor invasion during PTC progression.
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Affiliation(s)
- Garcilaso Riesco-Eizaguirre
- Instituto de Investigaciones Biomédicas Alberto Sols Consejo Superior de Investigaciones Científicas y Universidad Autónoma de Madrid, Madrid, Spain
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82
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83
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Schweppe RE, Kerege AA, French JD, Sharma V, Grzywa RL, Haugen BR. Inhibition of Src with AZD0530 reveals the Src-Focal Adhesion kinase complex as a novel therapeutic target in papillary and anaplastic thyroid cancer. J Clin Endocrinol Metab 2009; 94:2199-203. [PMID: 19293266 PMCID: PMC2690419 DOI: 10.1210/jc.2008-2511] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Accepted: 03/06/2009] [Indexed: 11/19/2022]
Abstract
CONTEXT Focal adhesion kinase (FAK) and Src are overexpressed and activated in many cancers and have been associated with tumor progression. The role of the Src-FAK complex has not been characterized in papillary and anaplastic thyroid cancer (PTC and ATC). OBJECTIVE The goal of this study was to determine the role of Src and FAK in the growth and invasion of PTC and ATC. DESIGN PTC and ATC cells were treated with the oral Src inhibitor, AZD0530, to determine the consequences of Src inhibition using growth and invasion assays. FAK and phospho-FAK levels were analyzed in cell lines as well as in PTC tumor samples. RESULTS AZD0530 treatment inhibited the growth and invasion in four of five thyroid cancer cell lines, and inhibition did not correlate with basal levels of phospho-Src. Instead, we show for the first time that FAK, a critical substrate and effector of Src, is phosphorylated at tyrosine residue 861 (pY861) in PTC and ATC cells, and high levels of phospho-FAK correlate with AZD0530 sensitivity. We further showed that pY861-FAK phosphorylation is Src-dependent. Sensitivity to AZD0530 was confirmed using a preclinical three-dimensional culture model. Phospho-ERK1/2 was not affected by AZD0530, indicating that Src signaling does not require MAPK. Finally, FAK and pY861-FAK were expressed in 10 of 10 and five of 10 PTC tumors, respectively. CONCLUSIONS Inhibition of the Src-FAK complex represents a promising therapeutic strategy for patients with advanced thyroid cancer, and phospho-FAK represents a potential biomarker for response.
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Affiliation(s)
- Rebecca E Schweppe
- Division of Endocrinology, Diabetes, and Metabolism, University of Colorado Denver, Aurora, Colorado 80045, USA.
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84
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Knauf JA, Fagin JA. Role of MAPK pathway oncoproteins in thyroid cancer pathogenesis and as drug targets. Curr Opin Cell Biol 2009; 21:296-303. [PMID: 19231149 DOI: 10.1016/j.ceb.2009.01.013] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 01/16/2009] [Indexed: 12/24/2022]
Abstract
Constitutive activation of MAPK in cancer occurs through activating mutations or overexpression of upstream effectors in the pathway, primarily of genes encoding receptor tyrosine kinases, RAS and BRAF. Arguably, the evidence for MAPK activation is most compelling in thyroid cancers and in melanomas. In this review we discuss the mechanisms of tumor development by oncogenic BRAF in these two cancer cell lineages, since this kinase signals preferentially through this pathway. We describe recent information on the mediators of BRAF-induced tumor initiation and escape from senescence. In addition, we review the biochemical events implicated in cellular growth triggered by oncogenic BRAF and the determinants of oncogene addiction. The biology of thyroid cancers induced by oncogenic BRAF is quite distinct, both in humans and in mice. There is great interest in using these insights to design rational new therapies, for which it will become crucial to understand the determinants of sensitivity and resistance to compounds designed to block the pathway. In thyroid cancer, this interest is further heightened by new information on the role of activated BRAF and MAPK pathway activation in disrupting iodine transport and thyroid hormonogenesis.
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Affiliation(s)
- Jeffrey A Knauf
- Department of Medicine and Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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85
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Ryder M, Ghossein RA, Ricarte-Filho JCM, Knauf JA, Fagin JA. Increased density of tumor-associated macrophages is associated with decreased survival in advanced thyroid cancer. Endocr Relat Cancer 2008; 15:1069-74. [PMID: 18719091 PMCID: PMC2648614 DOI: 10.1677/erc-08-0036] [Citation(s) in RCA: 323] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Thyroid cancers are infiltrated with tumor-associated macrophages (TAMs), yet their role in cancer progression is not known. The objectives of this study were to characterize the density of TAMs in well-differentiated (WDTC), poorly differentiated (PDTC), and anaplastic thyroid cancers (ATC) and to correlate TAM density with clinicopathologic parameters. Immunohistochemistry was performed on tissue microarray sections from WDTC (n=33), PDTC (n=37), and ATC (n=20) using macrophage-specific markers. Electronic medical records were used to gather clinical and pathologic data. Follow-up information of PDTC patients was available for 0-12 years. In total, 9 out of 33 WDTC (27%), 20 out of 37 PDTC (54%), and 19 out of 20 ATC (95%) had an increased density of CD68(+) TAMs (> or = 10 per 0.28 mm(2); WDTC versus PDTC, P=0.03; WDTC versus ATC, P<0.0001; PDTC versus ATC, P<0.002). Increased TAMs in PDTC was associated with capsular invasion (P=0.034), extrathyroidal extension (P=0.009), and decreased cancer-related survival (P=0.009) compared with PDTC with a low density of TAMs. In conclusion, the density of TAMs is increased in advanced thyroid cancers. The presence of a high density of TAMs in PDTC correlates with invasion and decreased cancer-related survival. These results suggest that TAMs may facilitate tumor progression. As novel therapies directed against thyroid tumor cell-specific targets are being tested, the potential role of TAMs as potential modulators of the thyroid cancer behavior will need to be considered.
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Affiliation(s)
- Mabel Ryder
- Endocrinology Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 296, New York, New York 10021, USA.
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86
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Abstract
There is now a reasonably good understanding of the key oncogenic events involved in the initiation and progression of thyroid cancer. Many of these are characteristic of certain tumor types, and their presence conveys diagnostic and prognostic information. It is not yet clear how this information will be applied to clinical practice. Based on preclinical evidence, mutations of genes encoding certain kinases may also predict response to specific tyrosine kinase inhibitors, although this has not yet been explored systematically in clinical trials.
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Affiliation(s)
- James A Fagin
- Department of Medicine and Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA.
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87
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Weber GF. Molecular mechanisms of metastasis. Cancer Lett 2008; 270:181-90. [PMID: 18522865 DOI: 10.1016/j.canlet.2008.04.030] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 04/11/2008] [Accepted: 04/14/2008] [Indexed: 11/26/2022]
Abstract
Metastasis formation is an essential aspect of cancer, for which the molecular underpinning has long been subject to debate. Although the organ preference for dissemination is governed by tumor-host interactions on the epigenetic level there is a genetic basis to the ability of cancer cells to disseminate. Metastasis genes encode homing receptors, their ligands, and extracellular matrix-degrading proteinases, which jointly cause invasion and anchorage-independence. They are developmentally non-essential stress response genes that physiologically mediate the homing of immune system cells. Metastatic potential is conferred to cancer cells by aberrant expression or splicing of these genes. Oncogenes act upstream of metastasis genes. In cancer cells, oncogenic signaling activates distinct genetic programs leading to cell cycle progression and invasiveness, respectively. The expression of metastasis genes is regulated by multi-subunit transcription factor complexes. The identification of genes that direct cancer metastasis implicates them as candidate drug targets.
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Affiliation(s)
- Georg F Weber
- University of Cincinnati Academic Health Center, College of Pharmacy, 3225 Eden Avenue, Cincinnati, OH 45267-0004, USA.
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88
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Leboeuf R, Baumgartner JE, Benezra M, Malaguarnera R, Solit D, Pratilas CA, Rosen N, Knauf JA, Fagin JA. BRAFV600E mutation is associated with preferential sensitivity to mitogen-activated protein kinase kinase inhibition in thyroid cancer cell lines. J Clin Endocrinol Metab 2008; 93:2194-201. [PMID: 18381570 PMCID: PMC2435640 DOI: 10.1210/jc.2007-2825] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Mutually exclusive mutations of RET, RAS, or BRAF are present in about 70% of papillary thyroid carcinomas, whereas only the latter two are seen in poorly differentiated and anaplastic cancers. Although the signal output common to these oncoproteins is ERK, a recent report showed that only BRAF mutations consistently predicted responsiveness to MAPK kinase (MEK) inhibitors. OBJECTIVES Here we investigated whether sensitivity to MEK inhibition was determined by oncogene status in 13 human thyroid cancer cell lines: four with BRAF mutations, four RAS, one RET/PTC1, and four wild type. RESULTS Growth of BRAF (+) cells was inhibited by the MEK antagonist PD0325901 with an IC(50) of less than 5 nm. By contrast, RAS, RET/PTC1, or wild-type cells had IC(50) of 4 nm to greater than 1000 nm. Sensitivity was not predicted by coexisting mutations in PIK3CA or by PTEN status. Similar effects were obtained with the MEK inhibitor AZD6244. PD0325901 induced a sustained G1/S arrest in BRAF (+) but not BRAF (-) lines. PD0325901 was equipotent at inhibiting pERK1/2 after 2 h, regardless of genetic background, but pERK rebounded at 24 h in most lines. MEK inhibitor resistance was associated with partial refractoriness of pERK to further inhibition by the compounds. AZD6244 was more potent at inhibiting growth of NPA (BRAF +) than Cal62 (KRAS +) xenografts. CONCLUSION Thyroid cancers with BRAF mutation are preferentially sensitive to MEK inhibitors, whereas tumors with other MEK-ERK effector pathway gene mutations have variable responses, either because they are only partially dependent on ERK and/or because feedback responses elicit partial refractoriness to MEK inhibition.
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Affiliation(s)
- Rebecca Leboeuf
- Department of Medicine and Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA
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89
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Puxeddu E, Durante C, Avenia N, Filetti S, Russo D. Clinical implications of BRAF mutation in thyroid carcinoma. Trends Endocrinol Metab 2008; 19:138-45. [PMID: 18337114 DOI: 10.1016/j.tem.2007.12.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 12/05/2007] [Accepted: 12/13/2007] [Indexed: 10/22/2022]
Abstract
Significant progress has recently been made in the clinical management of papillary thyroid carcinoma. The accuracy of diagnosis and prognostic stratification of this type of carcinoma are high but still fall below 100%. Lack of effective treatments for advanced stage papillary thyroid carcinoma leads to death in some patients. Approximately half of all such carcinomas harbor mutations in the gene encoding the serine/threonine-kinase B-type Raf kinase (BRAF), resulting in constitutive activation of the mitogen-activated protein kinase-extracellular-signal-regulated kinases signal transduction pathway. There is intriguing evidence that BRAF mutation testing of papillary thyroid carcinoma might improve the diagnosis, prognostic stratification and treatment of these tumors but large, prospective trials are needed to define the actual clinical impact of these approaches.
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Affiliation(s)
- Efisio Puxeddu
- Department of Internal Medicine, University of Perugia, Via Enrico dal Pozzo, 06126 Perugia, Italy.
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90
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Abstract
Thyroid cancers stand out among solid tumours because many of the tumour-initiating genetic events have been identified. Mutations leading to constitutive activation of MAP kinase effectors -the tyrosine receptor kinase RET and the intracellular signalling effectors RAS and BRAF- are essential for the pathogenesis of papillary thyroid carcinoma (PTC). Similarly, there is increasing evidence demonstrating that mutations leading to activation of the phosphatidylinositol 3- kinase (PI3K)/AKT effectors -PTEN and PI3KCa- are essential for the pathogenesis of follicular thyroid carcinoma (FTC). Besides this strong relationship between the histological phenotype and the pathway predominantly activated, the nature of the genetic event seems to determine the biological behaviour of the tumour and the ultimate clinical outcome of the patient. In this review we will summarise and discuss the main genetic events related to thyroid cancer initiation, the contribution of genomics and the convenience of using a new molecular classification of thyroid cancer, complementary to the clinicopathological classification. This may help us to predict more faithfully the clinical outcome of patients with thyroid cancer and to select more appropriately candidates for targeted therapies.
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Affiliation(s)
- G Riesco-Eizaguirre
- Instituto de Investigaciones Biomédicas 'Alberto Sols' Consejo Superior de Investigaciones Científicas y Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
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91
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Xing M. BRAF mutation in papillary thyroid cancer: pathogenic role, molecular bases, and clinical implications. Endocr Rev 2007; 28:742-62. [PMID: 17940185 DOI: 10.1210/er.2007-0007] [Citation(s) in RCA: 695] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In recent years, the T1799A B-type Raf kinase (BRAF) mutation in thyroid cancer has received enthusiastic investigation, and significant progress has been made toward understanding its tumorigenic role and clinical significance. Among various thyroid tumors, this mutation occurs uniquely in papillary thyroid cancer (PTC), the most common endocrine malignancy, and some apparently PTC-derived anaplastic thyroid cancers. Many studies have found this mutation to be associated with those clinicopathological characteristics of PTC that are conventionally known to predict tumor progression and recurrence, including, for example, old patient age, extrathyroidal invasion, lymph node metastasis, and advanced tumor stages. Direct association of BRAF mutation with the clinical progression, recurrence, and treatment failure of PTC has also been demonstrated. The BRAF mutation has even been correlated with PTC recurrence in patients with conventionally low-risk clinicopathological factors. Some molecular mechanisms determining BRAF mutation-promoted progression and the aggressiveness of PTC have recently been uncovered. These include the down-regulation of major tumor suppressor genes and thyroid iodide-metabolizing genes and the up-regulation of cancer-promoting molecules, such as vascular endothelial growth factor, matrix metalloproteinases, nuclear transcription factor kappaB, and c-Met. Thus, BRAF mutation represents a novel indicator of the progression and aggressiveness of PTC. Significant advances have also occurred in the preclinical testing of new therapeutic strategies targeting the MAPK pathway aberrantly activated by BRAF mutation and other related mutations. New mitogen extracellular kinase (MEK) inhibitors developed recently are particularly promising therapeutic agents for thyroid cancer. With these advances, it has become clearer that BRAF mutation will likely have significant impact on the clinical management of PTC.
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Affiliation(s)
- Mingzhao Xing
- Division of Endocrinology and Metabolism, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
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92
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Lupi C, Giannini R, Ugolini C, Proietti A, Berti P, Minuto M, Materazzi G, Elisei R, Santoro M, Miccoli P, Basolo F. Association of BRAF V600E mutation with poor clinicopathological outcomes in 500 consecutive cases of papillary thyroid carcinoma. J Clin Endocrinol Metab 2007; 92:4085-90. [PMID: 17785355 DOI: 10.1210/jc.2007-1179] [Citation(s) in RCA: 284] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Because very few studies have examined the correlation between BRAF mutations and clinicopathological features of papillary thyroid carcinoma (PTC), we analyzed here a large and homogeneous cohort of patients with PTC for the presence of the BRAF mutation. OBJECTIVE We examined BRAF mutations in a consecutive series of 500 PTC patients who underwent surgery in the Department of Surgery of the University of Pisa, and we correlated the presence of the mutation with clinicopathological parameters of the patients: age, gender, tumor size, presence of tumor capsule, extrathyroidal invasion, multicentricity, presence of node metastases, and tumor class. DESIGN BRAF (exon 15) mutation was examined by PCR-single strand conformational polymorphism followed by DNA sequencing in laser-capture microdissected tissue samples. RESULTS In this study, BRAF mutation was found in 219 of 500 cases (43.8%). In particular, we found the most common BRAF V600E mutation in 214 cases (42.8%), BRAF K601E mutation in three cases (0.6%), BRAF VK600-1E (0.2%) in one case, whereas in one case we found a new 14-bp deletion with concomitant 2-bp insertion, VKSR600-3del and T599I, respectively. BRAF V600E was associated with extrathyroidal invasion (P < 0.0001), multicentricity (P = 0.0026), presence of nodal metastases (P = 0.0009), class III vs. classes I and II (P < 0.00000006), and absence of tumor capsule (P < 0.0001), in particular in follicular- and micro-PTC variants. By multivariate analysis, the absence of tumor capsule remained the only parameter associated (P = 0.0005) with BRAF V600E mutation. CONCLUSIONS Our data suggest that BRAF V600E mutation is associated with high-risk PTC and in particular in follicular variant with invasive tumor growth.
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Affiliation(s)
- Cristiana Lupi
- Departments of Surgery and Endocrinology, University of Pisa, 56126 Pisa, Italy
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93
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Kebebew E, Weng J, Bauer J, Ranvier G, Clark OH, Duh QY, Shibru D, Bastian B, Griffin A. The prevalence and prognostic value of BRAF mutation in thyroid cancer. Ann Surg 2007; 246:466-70; discussion 470-1. [PMID: 17717450 PMCID: PMC1959359 DOI: 10.1097/sla.0b013e318148563d] [Citation(s) in RCA: 343] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE To examine the prevalence of BRAF mutation among thyroid cancer histologic subtypes and determine the association of BRAF mutation with indicators of poor prognosis for papillary thyroid cancer and patient outcome. SUMMARY BACKGROUND DATA The appropriate extent of surgical treatment, adjuvant therapy and follow-up monitoring for thyroid cancer remains controversial. Advances in the molecular biology of thyroid cancer have helped to identify candidate markers of disease aggressiveness. A commonly found genetic alternation is a point mutation in the BRAF oncogene (BRAF V600E), which is primarily found in papillary thyroid cancer and is associated with more aggressive disease. METHODS BRAF V600E mutation status was determined in 347 tumor samples from 314 patients with thyroid cancer (245 with conventional papillary thyroid cancer, 73 with follicular thyroid cancer, and 29 with the follicular variant of papillary thyroid cancer). Univariate and multivariate analyses were performed to determine the association of BRAF V600E with clinicopathologic factors and patient outcome. RESULTS : The prevalence of BRAF V600E mutation was higher in conventional papillary thyroid cancer (51.0%) than in follicular variant of papillary thyroid cancer (24.1%) and follicular thyroid cancer (1.4%) (P < 0.0001). In patients with conventional papillary thyroid cancer, BRAF V600E mutation was associated with older age (P = 0.0381), lymph node metastasis (P = 0.0323), distant metastasis (P = 0.045), higher TNM stage (I and II vs. III and IV, P = 0.0389), and recurrent and persistent disease (P = 0.009) with a median follow-up time of 6.0 years. Multivariate analysis showed that BRAF V600E mutation [OR (95% CI) = 4.2 (1.2-14.6)] and lymph node metastasis [OR (95% CI) = 7.75 (2.1-28.5)] were independently associated with recurrent and persistent disease in patients with conventional papillary thyroid cancer. CONCLUSIONS BRAF V600E mutation is primarily present in conventional papillary thyroid cancer. It is associated with an aggressive tumor phenotype and higher risk of recurrent and persistent disease in patients with conventional papillary thyroid cancer. Testing for this mutation may be useful for selecting initial therapy and for follow-up monitoring.
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Affiliation(s)
- Electron Kebebew
- Department of Surgery, University of California, San Francisco, San Francisco, California 94143-1674, USA.
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94
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Michaloglou C, Vredeveld LCW, Mooi WJ, Peeper DS. BRAF(E600) in benign and malignant human tumours. Oncogene 2007; 27:877-95. [PMID: 17724477 DOI: 10.1038/sj.onc.1210704] [Citation(s) in RCA: 194] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Of the RAF family of protein kinases, BRAF is the only member to be frequently activated by mutation in cancer. A single amino acid substitution (V600E) accounts for the vast majority and results in constitutive activation of BRAF kinase function. Its expression is required to maintain the proliferative and oncogenic characteristics of BRAF(E600)-expressing human tumour cells. Although BRAF(E600) acts as an oncogene in the context of additional genetic lesions, in primary cells it appears to be associated rather with transient stimulation of proliferation. Eventually, BRAF(E600) signalling triggers cell cycle arrest with the hallmarks of cellular senescence, as is illustrated by several recent studies in cultured cells, animal models and benign human lesions. In this review, we will discuss recent advances in our understanding of the role of BRAF(E600) in benign and malignant human tumours and the implications for therapeutic intervention.
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Affiliation(s)
- C Michaloglou
- Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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95
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Puxeddu E, Moretti S. Clinical prognosis in BRAF-mutated PTC. ACTA ACUST UNITED AC 2007; 51:736-47. [PMID: 17891237 DOI: 10.1590/s0004-27302007000500011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Accepted: 02/10/2007] [Indexed: 11/22/2022]
Abstract
BRAF mutation has recently emerged as a potential prognostic marker for papillary thyroid carcinoma (PTC) due to several studies suggesting that it may condition the development of tumors with aggressive behavior. A study of the phenotypes of thyroid follicular cell lines and transgenic mice characterized by targeted expression of BRAF mutation indicates that, at variance with RET/PTC rearrangement, it induces or facilitates genomic instability and higher invasiveness and eventually deeper tumor de-differentiation and more significant suppression of apoptosis. An analysis of differential gene expression of PTCs harboring BRAF mutation versus PTCs characterized by other genetic alterations shows an important impairment of the expression of genes related to intra-thyroidal iodine metabolism machinery, up-regulation of Glut-1 mRNA, methylation-induced gene silencing of tumor suppressor genes and up-regulation of pro-angiogenetic proteins such as VEGF. Correlation of BRAF mutation with PTC clinico-pathological features yields controversial results, with several studies showing the association with unfavourable clinico-pathological qualities, while others do not confirm the findings. This review will summarize the studies in favor of or in contrast with a role of BRAF mutation as a prognostic marker in PTC. We will also indicate what information we still need in order to routinely introduce this indicator in clinical practice.
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Affiliation(s)
- Efisio Puxeddu
- Department of Internal Medicine, Center for Thyroid Proteomic and Genomic Research, University of Perugia, and Regional Oncology Referral Center, Santa Maria della Misericordia Hospital, Italy.
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Mitsiades CS, Negri J, McMullan C, McMillin DW, Sozopoulos E, Fanourakis G, Voutsinas G, Tseleni-Balafouta S, Poulaki V, Batt D, Mitsiades N. Targeting BRAFV600E in thyroid carcinoma: therapeutic implications. Mol Cancer Ther 2007; 6:1070-8. [PMID: 17363500 DOI: 10.1158/1535-7163.mct-06-0449] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
B-Raf is an important mediator of cell proliferation and survival signals transduced via the Ras-Raf-MEK-ERK cascade. BRAF mutations have been detected in several tumors, including papillary thyroid carcinoma, but the precise role of B-Raf as a therapeutic target for thyroid carcinoma is still under investigation. We analyzed a panel of 93 specimens and 14 thyroid carcinoma cell lines for the presence of BRAF mutations and activation of the mitogen-activated protein/ERK kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway. We also compared the effect of a B-Raf small inhibitory RNA construct and the B-Raf kinase inhibitor AAL881 on both B-Raf wild-type and mutant thyroid carcinoma cell lines. We found a high prevalence of the T1799A (V600E) mutation in papillary and anaplastic carcinoma specimens and cell lines. There was no difference in patient age, B-Raf expression, Ki67 immunostaining, or clinical stage at presentation between wild-type and BRAF(V600E) specimens. Immunodetection of phosphorylated and total forms of MEK and ERK revealed no difference in their phosphorylation between wild-type and BRAF(V600E) patient specimens or cell lines. Furthermore, a small inhibitory RNA construct targeting the expression of both wild-type B-Raf and B-Raf(V600E) induced a comparable reduction of viability in both wild-type and BRAF(V600E) mutant cancer cells. Interestingly, AAL881 inhibited MEK and ERK phosphorylation and induced apoptosis preferentially in BRAF(V600E)-harboring cells than wild-type ones, possibly because of better inhibitory activity against B-Raf(V600E). We conclude that B-Raf is important for the pathophysiology of thyroid carcinomas irrespective of mutational status. Small molecule inhibitors that selectively target B-Raf(V600E) may provide clinical benefit for patients with thyroid cancer.
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MESH Headings
- Adenocarcinoma, Follicular/genetics
- Adenocarcinoma, Follicular/pathology
- Adenocarcinoma, Follicular/prevention & control
- Adult
- Aged
- Apoptosis/drug effects
- Carcinoma/genetics
- Carcinoma/pathology
- Carcinoma/prevention & control
- Carcinoma, Papillary/genetics
- Carcinoma, Papillary/pathology
- Carcinoma, Papillary/prevention & control
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/pathology
- Carcinoma, Squamous Cell/prevention & control
- Cell Proliferation/drug effects
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Female
- Humans
- Isoquinolines/pharmacology
- Male
- Middle Aged
- Mitogen-Activated Protein Kinases/metabolism
- Mutation/genetics
- Phosphorylation/drug effects
- Proto-Oncogene Proteins B-raf/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/drug effects
- Thyroid Neoplasms/genetics
- Thyroid Neoplasms/pathology
- Thyroid Neoplasms/prevention & control
- Tumor Cells, Cultured/drug effects
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Affiliation(s)
- Constantine S Mitsiades
- Department of Medical Oncology, Dana-Farber Cancer Institute, Mayer Building, Room M555, 44 Binney Street, Boston, MA 02115, USA.
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97
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Espinosa AV, Porchia L, Ringel MD. Targeting BRAF in thyroid cancer. Br J Cancer 2007; 96:16-20. [PMID: 17179987 PMCID: PMC2360215 DOI: 10.1038/sj.bjc.6603520] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 11/09/2006] [Accepted: 11/10/2006] [Indexed: 11/16/2022] Open
Abstract
Activating mutations in the gene encoding BRAF are the most commonly identified oncogenic abnormalities in papillary thyroid cancer. In vitro and in vivo models have demonstrated that overexpression of activated BRAF induces malignant transformation and aggressive tumour behaviour. BRAF and other RAF kinases are frequently activated by other thyroid oncogenes and are important mediators of their biological effects including dedifferentiation and proliferation. Because current therapeutic options for patients with thyroid cancers that are aggressive and/or do not respond to standard therapies are limited, BRAF and its downstream effectors represent attractive therapeutic targets. In this review, data supporting a role for BRAF activation in thyroid cancer development and establishing the potential therapeutic efficacy of BRAF-targeted agents in patients with thyroid cancer will be reviewed.
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Affiliation(s)
- A V Espinosa
- Divisions of Endocrinology and Oncology, Department of Medicine, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, OH, USA
| | - L Porchia
- Divisions of Endocrinology and Oncology, Department of Medicine, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, OH, USA
| | - M D Ringel
- Divisions of Endocrinology and Oncology, Department of Medicine, The Ohio State University College of Medicine and Arthur G. James Comprehensive Cancer Center, Columbus, OH, USA
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98
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Vasko VV, Saji M. Molecular mechanisms involved in differentiated thyroid cancer invasion and metastasis. Curr Opin Oncol 2007; 19:11-7. [PMID: 17133106 DOI: 10.1097/cco.0b013e328011ab86] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE OF REVIEW The majority of patients with thyroid cancer have an excellent prognosis, however patients with extensive local invasion and distant metastasis frequently do not respond to standard treatments and have worsened prognosis. Understanding the specific mechanisms involved in thyroid cancer invasion and metastasis is critical in order to develop new treatments specifically targeted for these patients. RECENT FINDINGS The genetic basis for thyroid cancer initiation and development is well characterized, with the majority of studies implicating activation of the RAS-RAF-ERK and PI3K/PDK1/Akt signaling pathways. Over the last several years, data from a concerted effort to define the pathways involved in invasion and metastasis suggest that reactivation of embryonic pathways involved in cell movement, to include epithelial to mesenchymal transition and collective cell migration, may be involved in cancer cell migration and invasion. The previously identified thyroid oncogenes, BRAF, RET/PTC and Ras, appear to be important regulators of this process. SUMMARY The molecular mechanisms that control cell migration during embryological development, such as epithelial to mesenchymal transition, appear to be reactivated in invading thyroid cancer cells. Elucidation of the signal-transduction networks and molecules that are involved in thyroid cancer invasion may lead to novel therapeutic targets.
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Affiliation(s)
- Vasyl V Vasko
- Department of Pediatrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA.
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Yeh MW, Rougier JP, Park JW, Duh QY, Wong M, Werb Z, Clark OH. Differentiated thyroid cancer cell invasion is regulated through epidermal growth factor receptor-dependent activation of matrix metalloproteinase (MMP)-2/gelatinase A. Endocr Relat Cancer 2006; 13:1173-83. [PMID: 17158762 PMCID: PMC2574514 DOI: 10.1677/erc.1.01226] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Mechanisms of invasion in thyroid cancer remain poorly understood. We hypothesized that signaling via the epidermal growth factor receptor (EGFR) stimulates thyroid cancer cell invasion by altering the expression and cleavage of matrix metalloproteinases (MMPs). Papillary and follicular carcinoma cell lines were treated with EGF, the EGFR tyrosine kinase inhibitor AG1478, and the MMP inhibitors GM-6001 and Col-3. Flow cytometry was used to detect EGFR. In vitro invasion assays, gelatin zymography, and quantitative reverse transcription-PCR were used to assess the changes in invasive behavior and MMP expression and activation. All cell lines were found to overexpress functional EGFR. EGF stimulated invasion by thyroid cancer cells up to sevenfold (P<0.0001), a process that was antagonized completely by AG1478 and Col-3, partially by GM-6001, but not by the serine protease inhibitor aprotinin. EGF upregulated expression of MMP-9 (2.64- to 8.89-fold, P<0.0001) and membrane type-1 MMP (MT1-MMP, 1.97- to 2.67-fold, P<0.0001). This effect was blocked completely by AG1478 and partially by Col-3. The activation of MMP-2 paralleled MT1-MMP expression. We demonstrate that MMPs are critical effectors of invasion in the papillary and follicular thyroid cancer cell lines studied. Invasion is regulated by signaling through EGFR, an effect mediated by augmentation of gelatinase expression and activation. MMP inhibitors and growth factor antagonists may be effective tumoristatic agents for the treatment of aggressive thyroid carcinomas.
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Affiliation(s)
- Michael W Yeh
- Endocrine Surgery Laboratory, UCSF/Mt. Zion Medical Center, San Francisco, California 94115, USA.
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