Open Access Research

Effect of ret/PTC 1 rearrangement on transcription and post-transcriptional regulation in a papillary thyroid carcinoma model

Susanne Cahill1, Paul Smyth1, Stephen P Finn1, Karen Denning1, Richard Flavin1, Esther M O'Regan2, Jinghuan Li1, Astrid Potratz3, Simone M Guenther3, Richard Henfrey3, John J O'Leary1 and Orla Sheils1*

Author Affiliations

1 Dept. of Histopathology, University of Dublin, Trinity College, Dublin, Ireland

2 Dept. of Pathology, Dublin Dental School and Hospital, Dublin, Ireland

3 Applied Biosystems, Foster City, CA, USA

For all author emails, please log on.

Molecular Cancer 2006, 5:70  doi:10.1186/1476-4598-5-70

Published: 11 December 2006

Abstract

Background

microRNAs (miRNAs) are a group of non-coding single stranded RNAs measuring approximately 22 nt in length that have been found to control cell growth, differentiation and apoptosis. miRNAs negatively regulate their target genes and recently have been implicated in tumourigenesis. Furthermore, miRNA expression profiling correlates with various cancers, with these genes thought to act as both tumour suppressors and oncogenes. ret/PTC 1 is an oncogene with constitutive kinase activity implicated in the development of papillary thyroid carcinoma (PTC). This rearrangement leads to aberrant MAPK activation that is implicated in PTC tumourigenesis.

Aim

The aim of this study was to identify the effect that ret/PTC 1 has on transcription and post-transcriptional regulation in PTC by using DNA microarray and microRNA analysis.

Results

DNA microarray analysis revealed a group of genes differentially expressed between normal thyroid cell lines and those harbouring a ret/PTC 1 rearrangement.

Furthermore, a unique miRNA expression signature differentiated between PTC cell lines with ret/PTC 1 and a normal thyroid cell line. 21 miRNAs showed significant overexpression and 14 miRNAs showed underexpression in these cell lines when compared to normal thyroid. Several of these up/down regulated miRNAs may be involved in PTC pathogenesis.