Endocrine Abstracts

Monitoring patients with thyroid cancer for recurrent disease relies heavily on measuring serum thyroglobulin (Tg). Tg cannot be assessed reliably in the presence of anti-thyroglobulin antibodies for analytical reasons, this being the case in about a third of patients. There has been recent interest in microRNA profiling of fine needle aspiration biopsies of thyroid nodules, with encouraging results. The objective of this pilot was to explore microRNAs in peripheral blood of patients with papillary thyroid cancer (PTC). Sera from ninety patients with PTC were studied. They were divided into three equal groups based on clinical, radiological, biochemical (serum Tg) and cytological/histological assessments: i) recurrent/metastatic thyroid cancer, ii) athyreotic with no evidence of recurrent thyroid cancer, iii) known thyroid remnant, no evidence of recurrent thyroid cancer. Real-time PCR panel analysis of microRNAs was performed. Each RNA sample was reverse transcribed (RT) into cDNA and run on the miRCURY LNATM Universal RT miRNA PCR Human panel I and II. Eighteen microRNAs of potential interest emerged (P<0.05). hsa-miR-484 was associated with the highest statistical significance (P<0.001) for discriminating between patients with metastatic/recurrent PTC and the other two groups. hsa-miR-484 has not been previously described as a marker of thyroid cancer, although it is implicated in breast, ovarian, pancreatic cancer and malignant melanoma. Serum levels of three other microRNAs previously reported to be differentially expressed in thyroid cancer tissue (miR-122-5p, miR-885-5p, miR-17-5p), were also found to be associated with recurrent/metastatic thyroid cancer. This pilot has identified potential microRNAs in peripheral blood of patients with PTC that could potentially be used as markers for recurrent/metastatic disease. Further larger studies are required to confirm these findings.