TC cell transfection with LEMD1 siRNA or overexpression vector reveals that LEMD1 promotes TC cell proliferation. (A) Relative mRNA and protein LEMD1 expression in HTORI-3 (normal human thyroid cell line) and three TC cell lines. (B) LEMD1 expression was detected via RT-qPCR and WB in TPC-1, BCPAP and KTC-1 cell lines transfected with siRNA. (C) Transfection efficiency of LEMD1 overexpression vector in TC cell lines detected via RT-qPCR and WB. Results of colony formation assays for TC cells transfected with (D) Si-LEMD1 or (E) LEMD1 OE vector. (F) Cell proliferation was measured using the Cell Counting Kit-8 assay in TC cells transfected with Si-LEMD1 or LEMD1 OE vector. The data are shown as the mean ± SD of three independent experiments. Statistical significance was evaluated using one-way ANOVA followed by Tukey's post-hoc test for comparisons among multiple groups or Student's unpaired t-test for comparisons between two groups. *P<0.05, **P<0.01, ***P<0.001 and ****P<0.0001 vs. HTORI-3, Si-NC or control. LEMD1, LEM domain containing 1; TC, thyroid cancer; siRNA, small interfering RNA; RT-qPCR, reverse transcription quantitative PCR; OE, overexpression; WB, western blot; NC, negative control; OD, optical density.