2.3. Transient transfection

Rspo2 siRNA or LGR4 siRNA (50 nM, GenePharma, Shanghai, China), and the negative controls (siNC) were transfected into TSCC cells using the Lipofectamine RNAiMAX Transfection Reagent (Invitrogen, CA, USA) according to the manufacturer's instructions. The efficiency of transfection was evaluated by Quantitative real-time PCR (qRT-PCR) and Western blotting. The Rspo2 and LGR4 siRNA sequences were shown in Supplementary Table 1.