TUSC3 and gastric cancer: By performing the following dual-luciferase reporter gene system assay, we validated that miR-224-5p targeted both LncRNA MIR503HG (Figures 3B, C) and 3’ UTR of TUSC3 mRNA (Figures 3E, F), which were supported by the RNA pull-down assay results that miR-224-5p could be enriched by both biotin-labelled LncRNA MIR503HG (Figures S6A, B) and TUSC3 (Figures S6C, D) in GC cells.