CONTEXT: BRAF mutations are common in papillary thyroid carcinomas (PTCs). By affecting the expression of genes critically related to the development and differentiation of thyroid cancer, they may influence the prognosis of these tumors. OBJECTIVE: Our objective was to characterize the expression of thyroid-specific genes associated with BRAF mutation in PTCs. DESIGN/SETTING AND PATIENTS: We examined the expression of key markers of thyrocyte differentiation in 56 PTCs with BRAF mutations (BRAF-mut) and 37 with wild-type BRAF (BRAF-wt). Eight samples of normal thyroid tissue were analyzed as controls. Quantitative PCR was used to measure mRNA levels for the sodium/iodide symporter (NIS), apical iodide transporter (AIT-B), thyroglobulin (Tg), thyroperoxidase (TPO), TSH receptor (TSH-R), the transcription factor PAX8, and glucose transporter type 1 (Glut1). NIS protein expression and localization was also analyzed by immunohistochemistry. RESULTS: mRNA levels for all thyroid-specific genes were reduced in all PTCs vs. normal thyroid tissues. NIS, AIT-B, Tg, and TPO expression was significantly lower in BRAF-mut tumors than in the BRAF-wt group. Glut-1 transcript levels were increased in all PTCs, and additional increases were noted in BRAF-mut tumors. In both tumor subsets, the NIS protein that was expressed was abnormally retained in the cytoplasm. CONCLUSION: BRAF V600E mutation in PTCs is associated with reduced expression of key genes involved in iodine metabolism. This effect may alter the effectiveness of diagnostic and/or therapeutic use of radioiodine in BRAF-mut PTCs.
CONTEXT: BRAF mutations are common in papillary thyroid carcinomas (PTCs). By affecting the expression of genes critically related to the development and differentiation of thyroid cancer, they may influence the prognosis of these tumors. OBJECTIVE: Our objective was to characterize the expression of thyroid-specific genes associated with BRAF mutation in PTCs. DESIGN/SETTING AND PATIENTS: We examined the expression of key markers of thyrocyte differentiation in 56 PTCs with BRAF mutations (BRAF-mut) and 37 with wild-type BRAF (BRAF-wt). Eight samples of normal thyroid tissue were analyzed as controls. Quantitative PCR was used to measure mRNA levels for the sodium/iodide symporter (NIS), apical iodide transporter (AIT-B), thyroglobulin (Tg), thyroperoxidase (TPO), TSH receptor (TSH-R), the transcription factor PAX8, and glucose transporter type 1 (Glut1). NIS protein expression and localization was also analyzed by immunohistochemistry. RESULTS: mRNA levels for all thyroid-specific genes were reduced in all PTCs vs. normal thyroid tissues. NIS, AIT-B, Tg, and TPO expression was significantly lower in BRAF-mut tumors than in the BRAF-wt group. Glut-1 transcript levels were increased in all PTCs, and additional increases were noted in BRAF-mut tumors. In both tumor subsets, the NIS protein that was expressed was abnormally retained in the cytoplasm. CONCLUSION:BRAFV600E mutation in PTCs is associated with reduced expression of key genes involved in iodine metabolism. This effect may alter the effectiveness of diagnostic and/or therapeutic use of radioiodine in BRAF-mut PTCs.
Authors: Thomas J Musholt; Sonja Schönefeld; Christina H Schwarz; Felix M Watzka; Petra B Musholt; Christian Fottner; Matthias M Weber; Erik Springer; Arno Schad Journal: Langenbecks Arch Surg Date: 2010-07-18 Impact factor: 3.445
Authors: Tania Jaber; Steven G Waguespack; Maria E Cabanillas; Mohamed Elbanan; Thinh Vu; Ramona Dadu; Steven I Sherman; Moran Amit; Elmer B Santos; Mark Zafereo; Naifa L Busaidy Journal: J Clin Endocrinol Metab Date: 2018-10-01 Impact factor: 5.958
Authors: James Nagarajah; Mina Le; Jeffrey A Knauf; Giuseppe Ferrandino; Cristina Montero-Conde; Nagavarakishore Pillarsetty; Alexander Bolaender; Christopher Irwin; Gnana Prakasam Krishnamoorthy; Mahesh Saqcena; Steven M Larson; Alan L Ho; Venkatraman Seshan; Nobuya Ishii; Nancy Carrasco; Neal Rosen; Wolfgang A Weber; James A Fagin Journal: J Clin Invest Date: 2016-09-26 Impact factor: 14.808