title: MicroRNAs let7 expression in thyroid cancer: correlation with their deputed targets HMGA2 and SLC5A5.
abstract: OBJECTIVE
  Thyroid cancer (TC), the most common endocrine malignancy, increases its incidence worldwide. MicroRNAs have been shown to be abnormally expressed in tumors and could represent valid diagnostic markers for patients affected by TC. Our aim was to analyze the expression of tumorsuppressor hsa-let7b-5p and hsa-let7f-5p, together with their predicted targets SLC5A5 (NIS) and HMGA2, in papillary (PTC), follicular (FTC) and anaplastic (ATC).
  
  
  METHODS
  8 FTC, 14 PTC, 12 ATC and three normal thyroid tissue samples were analyzed for the expression of pre-let7b, hsa-let7b-5p and hsa-let7f-5p as SLC5A5 and HMGA2 by RT-qPCR. Data were analyzed by REST 2008.
  
  
  RESULTS
  FTC patients showed a significant down-regulation of hsa-let7b-5p and its precursor. hsa-let7f-5p was overexpressed, and SLC5A5 was strongly suppressed. HMGA2 was overexpressed, reflecting no correlation with its regulatory let7 miRNAs. PTC samples were characterized by up-regulation of hsa-let7b-5p, its precursor and hsa-let7f-5p. SLC5A5 was strongly suppressed in comparison with normal thyroid tissue. HMGA2 was overexpressed, as shown in FTC, also. ATC samples showed a similar miRNAs profile as PTC. In contrast with FTC and PTC, these patients showed a stable or up-regulated SLC5A5 and HMGA2.
  
  
  CONCLUSIONS
  Expression of HMGA2 is not correlated with the regulatory let7 miRNAs. Interestingly, SLC5A5 was down-regulated in FTC and PTC. Its expression could be modulated by hsa-let-7f-5p. ATC showed a loss of SLC5A5/hsa-let7f-5p correlation. SLC5A5, in ATC, needs further investigation to clarify the genetic/epigenetic mechanism altering its expression.
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Damanakis
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Eckhardt
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Wunderlich
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Silvia
authors.initials: S
authors.lastname: Roth
authors.affiliation: Division of Gastroenterology and Endocrinology, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Thaddeus T
authors.initials: TT
authors.lastname: Wissniowski
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany.
authors.forename: Detlef K
authors.initials: DK
authors.lastname: Bartsch
authors.affiliation: Department of Visceral, Thoracic and Vascular Surgery, Philipps University Marburg, Baldingerstrasse, 35043, Marburg, Germany. difazio@med.uni-marburg.de.
authors.forename: Pietro
authors.initials: P
authors.lastname: Di Fazio
mesh_terms: D025743:HMGA2 Protein / Q000378:metabolism*; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D027981:Symporters / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000378:metabolism; D000099209:Sodium-Iodide Symporters
chemical_list: D025743:HMGA2 Protein; D035683:MicroRNAs; D027981:Symporters; D000099209:Sodium-Iodide Symporters
keywords: Diagnostic markers; Epigenetic; Thyroid cancer; let7; miRNAs