Abstract
Possible interference of fibroblasts is suggested in aspiration biopsy nucleic acid diagnosis (ABND). However, detection of fibroblasts in the aspirates is difficult, because the gene expression profiles of thyroid malignancies and fibroblasts are much alike in many aspects. To identify a specific marker for thyroid-derived fibroblasts, the data of the serial analysis of gene expression (SAGE) were compared to screen differentially expressed genes between fibroblasts and thyroid normal and tumor tissues. In the SAGE data, 5 genes were identified to be differentially expressed. Among these, thrombospondin 1 (TSP-1, THBS1) mRNA was the most differentially expressed. Further, the overexpression of TSP-1 mRNA in fibroblasts was confirmed by real-time RT-PCR analysis using 73 thyroid normal and tumor tissues and 7 cultures of thyroid-derived fibroblasts. These results suggest that TSP-1 mRNA is a possible marker for contamination of thyroid-derived fibroblasts.
