Figure 1. Strategy for identifying potential PTC biomarkers.

Schematic representation of the experimental design used in this study. We first applied a GeLC-MS/MS approach to comprehensively analyze the proteome profiles of thyroid cystic fluid samples from PTC and benign lesions, as well as the secretome profiles of two PTC cell lines. Meanwhile, we searched public-domain transcriptome datasets for genes whose transcriptional levels were up-regulated in PTC tissues. We then integrated the three datasets to identify candidate genes/proteins that were selectively detected in the PTC cystic fluid samples, highly up-regulated in PTC tissues, and secreted/released from PTC cells. Finally, we verified the candidate proteins in FNA cystic fluid and PTC tissue samples using immunoblotting and immunohistochemistry.