The effects of human TSH receptor gene transfection on iodide uptake and thyroid-specific gene expression in poorly differentiated thyroid carcinoma cell line / 中华核医学杂志

ABSTRACT

Objective To investigate the changes of iodide uptake and the expression of thyroidspecific genes in poorly differentiated follicular thyroid carcinoma (FTC) cells after transfection of human TSH receptor (hTSHR) gene in vitro. Methods The recombinant eukaryotic expression plasmid PcDNA3. 1/hTSHR-cDNA was transformed into DH5a bacterial for amplification and then the recombinant plasmid was extracted. The recombinant was identified with PCR amplifying, restriction enzyme digestion analysis and DNA sequencing. The recombinant plasmid pcDNA3.1/hTSHR was transfected into FTC-133 cell line by lipofectin methodin vitro. Immunofluorescence, iodide uptake studies and real time-PCR were applied to detect target protein expression. Statistical analysis was performed with t-test using SPSS 13. 0 software. Results Kpn Ⅰ and Xba Ⅰ restriction enzyme digestion, PCR amplifying and DNA sequencing confirmed that pcDNA3. 1/hTSHR was successfully constructed. After transfection of the recombinant plasmid pcDNA3. 1/hTSHR-cDNA and the stimulation of hTSH, the tumor cells displayed the expression of hTSHR protein at cell surface and cytoplasm. The iodine uptake in pcDNA3. 1/hTSHR transfected cells was 2. 9 times higher than that of control(pcDNA3.1(+) transfected cells) group(t = 28.63, P ＜0. 01). The expression of TSHR,NIS, TPO and Tg (mRNA levels) in pcDNA3. 1/hTSHR transfected cells were also significantly elevated by 1.74 (t =5.959, P＜0.01), 7.2 (t =3.807,P＜0.05), 2.88 (t=4.769,P＜0. 01) and 2.67 times (t=6.388,P ＜0.01) respectively compared to those of the control group. Conclusion The study demonstrates that iodide uptake may be reactivated by hTSHR receptor gene transfection in poorly differentiated FTC cell.