miR-210 de-regulated FGFRL1 expression via binding to the 3′-UTR of FGFRL1 directly. (A) The miR-210 binding sequence in the 3′-UTR of FGFRL1. (B and C) The luciferase reporter gene assays were performed to detect the fluorescence activities of the FGFRL1 3′UTR in MG63 cells (B) and Saos-2 cells (C) which were cotransfected with wild-type FGFRL1 3′UTR or mutational type FGFRL1 3′UTR and miR-210, respectively (**P<0.01). (D and E) RT-qPCR results of the FGFRL1 mRNA level in MG63 cells (D) and Saos-2 cells (E) with different transfections (**P<0.01 as indicated). (F) Western blot results of the FGFRL1 expression in osteosarcoma cells with different transfections. miR, microRNA; FGFRL1, fibroblast growth factor receptor-like 1; 3′-UTR, 3′untranslated region; RT-qPCR, reverse transcription-quantitative polymerase chain reaction.