Identification of Differentially Expressed Genes in Papillary Thyroid Carcinomas With and Without Rearrangements of the Tyrosine Kinase Receptors RET and/or NTRK1

Background The transforming capacities of RET and/or NTRK1 chimeric oncogenes as well as the molecular background of non-rearranged papillary thyroid carcinomas (PTCs) remain to be elucidated. To assess altered gene expression, we examined PTCs with and without tyrosine kinase receptor rearrangements by mRNA differential display (DD). Materials and methods Six of 13 PTCs examined harbored RET chimeras (3× RET/PTC1, 1× RET/PTC3) and/or NTRK1 chimeras (2× trk, 1× TRK-T3, 2 unknown TRK hybrids). The method of DD analysis was refined by a novel fragment-recovery technique using a high-performance fluorescence scanner. Results Of 500 up- or down-regulated mRNA transcripts, 19 selected fragments …