Hyalinizing trabecular tumour of the thyroid-differential expression of distinct miRNAs compared with papillary thyroid carcinoma

Histopathology. 2010 Apr;56(5):632-40. doi: 10.1111/j.1365-2559.2010.03526.x.

Abstract

Aims: To compare the expression pattern of five microRNAs (miRNAs) (146b, -181b, -21, -221, -222) of papillary thyroid carcinoma (PTC) and hyalinizing trabecular tumour of the thyroid (HTT).

Methods and results: The expression pattern of five miRNAs known to be up-regulated in PTC was retrospectively analysed in 18 HTTs, adjacent normal thyroid tissue, 10 PTCs, 10 follicular adenomas and 10 non-toxic multinodular goitres (MNG) by reverse transcriptase-polymerase chain reaction using the TaqMan miRNA assay. Furthermore, the two common genetic alterations characteristic for PTC, the V600E mutation of the BRAF gene and RET/PTC 1 and 3 rearrangements, were determined in all HTTs. All miRNAs were significantly up-regulated in PTCs, whereas all miRNAs in HTT, normal thyroid tissue, adenomas, and MNGs were down-regulated. Calculating relative changes in gene expression, a 510-fold change of miRNA 146b between PTC and HTT could be observed followed by fold changes between 6.4 and 29 in the remaining miRNAs (P < 0.001). All HTTs lacked BRAF mutations and RET/PTC rearrangements.

Conclusions: Our findings do not support the concept that a high proportion of HTT represents a variant of PTC. It is suggested that HTTs lacking both a miRNA expression pattern characteristic for PTC and RET/PTC rearrangements are re-designated as 'hyalinizing trabecular adenomas'.

Publication types

  • Comparative Study

MeSH terms

  • Adenocarcinoma, Papillary / genetics*
  • Adenocarcinoma, Papillary / metabolism
  • Adenocarcinoma, Papillary / pathology
  • Adenoma / genetics*
  • Adenoma / metabolism
  • Adenoma / pathology
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic
  • Gene Rearrangement
  • Goiter, Nodular / genetics
  • Goiter, Nodular / metabolism
  • Goiter, Nodular / pathology
  • Humans
  • Hyalin / metabolism
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Mutation
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / metabolism
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism
  • Proto-Oncogene Proteins B-raf / genetics
  • Proto-Oncogene Proteins B-raf / metabolism
  • Retrospective Studies
  • Thyroid Gland / metabolism
  • Thyroid Gland / pathology
  • Thyroid Neoplasms / genetics*
  • Thyroid Neoplasms / metabolism
  • Thyroid Neoplasms / pathology

Substances

  • MicroRNAs
  • Oncogene Proteins, Fusion
  • Protein-Tyrosine Kinases
  • ret-PTC fusion oncoproteins, human
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf