ABSTRACT
Objective Forkhead box Q1 (FOXQ1) is highly expressed but its biological role remains unclear in papillary thyroid carcinoma (PTC). This article aims to investigate the effect of FOXQ1-siRAN on the proliferation of TPC-1 cells and its possible mechanism.Methods Synthetic FOXQ1-siRNA and NC-siRNA were transfected into TPC-1 cells by lipofectamineTM2000. The cells were divided into five groups: NC-siRAN, FOXQ1-1, FOXQ1-2, FOXQ1-3 and blank control. After transfection, the expressions of the FOXQ1 mRNA and protein, as well as those of c-Myc and cyclinD1 proteins, were determined by qRT-PCR and Western blot, and the changes in the proliferation of the TPC-1 cells observed by MTT.Results Compared with the blank control and NC-siRAN groups, the FOXQ1-3 group showed a significantly inhibited expression of FOXQ1 mRNA (P<0.05). The protein expression of FOXQ1 was markedly decreased in the FOXQ1-1, FOXQ1-2 and FOXQ1-3 groups in comparison with that in the NC-siRAN group (0.54±0.07, 0.40±0.07 and 0.26±0.06 vs 0.78±0.08, P<0.05). The proliferation of the TPC-1 cells was remarkably lower in the FOXQ1-3 than in the blank control and NC-siRNA groups (P<0.05), and so were the relative protein expressions of c-Myc (0.57±0.04 vs 1.05±0.07 and 0.92±0.06, P<0.05) and cyclinD1 (0.51±0.10 vs 0.94±0.12 and 0.91±0.11,P<0.05).Conclusion Silencing the FOXQ1 gene can effectively inhibit the proliferation of TPC-1 cells in TPC, probably by suppressing the expressions of c-Myc and cyclinD1.