title: Gene expression analysis reveals evidence for increased expression of cell cycle-associated genes and Gq-protein-protein kinase C signaling in cold thyroid nodules.
abstract: In contrast to the molecular etiology of autonomously functioning thyroid nodules, the molecular cause of cold thyroid nodules (CTNs), their benign, functional inactive counterparts, are so far largely unknown. Because of the partially dedifferentiated phenotype of CTNs, alterations in signaling cascades that favor proliferation, but not differentiation, are likely candidates for tumor induction and progression. The importance of RAS mutations for the development of benign nodules with follicular histology is still in question. However, differentially expressed genes in the context of their signaling cascades could define aberrant signaling in CTNs. Therefore, we investigated gene expression in 22 CTNs and their normal surrounding tissue using Affymetrix GeneChips. Most prominently, data analysis revealed an increased expression of cell cycle-associated genes and a special relevance of protein kinase C signaling, whereas no evidence of RAS-MAPK signaling in CTNs was found. Moreover, we determined 31 differentially regulated genes in CTNs, including several histone mRNAs. Taken together, these results explain recent findings showing an increased proliferation in CTNs and draw attention to protein kinase C signaling, but away from RAS-MAPK signaling, as being involved in the etiology of CTNs.
authors.affiliation: III. Medical Department, University of Leipzig, Philipp-Rosenthal-Strasse 27, D-04103 Leipzig, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Eszlinger
authors.forename: Knut
authors.initials: K
authors.lastname: Krohn
authors.forename: Kerstin
authors.initials: K
authors.lastname: Berger
authors.forename: Jürgen
authors.initials: J
authors.lastname: Läuter
authors.forename: Siegfried
authors.initials: S
authors.lastname: Kropf
authors.forename: Martin
authors.initials: M
authors.lastname: Beck
authors.forename: Dagmar
authors.initials: D
authors.lastname: Führer
authors.forename: Ralf
authors.initials: R
authors.lastname: Paschke
mesh_terms: D002453:Cell Cycle / Q000235:genetics*; D005260:Female; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D011493:Protein Kinase C / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D016606:Thyroid Nodule / Q000235:genetics* / Q000473:pathology
chemical_list: D011493:Protein Kinase C; D043802:GTP-Binding Protein alpha Subunits, Gq-G11