Thyroid Stimulating Hormone Receptor Transcripts in Correlation with Clinical Parameters in Thyroid Carcinoma Patients

BACKGROUND: Differentiated thyroid carcinomas (DTC) preserve expression of thyroid stimulating hormone receptor (TSHR). AIM: The aim of our study was to evaluate the expression of mRNA-TSHR in peripheral blood of DTC patients, then to correlate the expression with clinical features: Serum thyroglobulin (sTg) value, initial staging and findings from the whole body scan (WBS), neck ultrasound (US), and total received dose of radioiodine therapy. MATERIALS AND METHODS: Forty patients were divided into three groups according to the treatment response: Patients with incomplete structural response (TCs), incomplete biochemical response (TCb), and excellent responders (TCr). Total RNA was isolated from peripheral blood and used for two-step reverse transcriptase-PCR with appropriate primers. Relative quantification using the ΔCt and 2–ΔΔCt and method was applied. sTg levels were evaluated with chemiluminescent assay. The statistical analysis was performed with Spearman Rank Order Correlation. RESULTS: We found that TCs patients expressed mRNA-TSHR by a 5.37-fold higher level than TCr patients, TCb patients expressed TSHR by an 8.88-fold higher level than TCr patients. A significant negative correlation was detected between sTg and ΔCt (CtTSHR - CtGAPDH) value (R = −0.475; p < 0.05), and between WBS/US findings and ΔCt (R= −0.321; p < 0.05). CONCLUSION: Our data revealed higher expression of mRNA-TSHR in peripheral blood of TCs and TCb compared to TCr patients and analysis revealed a significant correlation between mRNA-TSHR and sTg and US/WBS findings. Further studies with larger number of subjects and absolute quantification are needed for understanding the real meaning of mRNA-TSHR as a biomarker in DTC