Figure 3. DLG1-AS1 functions as a molecular sponge for miR-497 in PTC cells. (A) The expression of DLG1-AS1 was determined in cytoplasmic and nuclear fractions of TPC-1 and B-CPAP cells. (B) The predicted binding site and mutant sites between DLG1-AS1 and miR-497 are shown. (C) Dual-luciferase reporter assay revealed that the overexpression of miR-497 negatively regulated the luciferase activity of DLG1-AS1-WT, rather than DLG1-AS1-Mut. WT: wild-type, Mut: mutant type. (D) The association between DLG1-AS1 and miR-497 was determined in TPC-1 cells by RNA pull-down assay. (E) Increased expression of miR-497 in TPC-1 cells transfected with sh-DLG1-AS1 or sh-NC. (F) The expression of DLG1-AS1 was determined in TPC-1 cells transfected with miR-497 mimics or miR-NC. (G) The expression of miR-497 is downregulated in PTC tissues as compared with that in adjacent normal tissues. (H) Quantitative real-time reverse transcription-polymerase chain reaction (qPCR) assays showing reduced expression of miR-497 in four PTC cell lines as compared with that in a normal thyroid epithelial cell line (Nthy-ori 3-1). (I) Analysis of correlation between DLG1-AS1 and miR-497 expression in PTC tissues by Pearson’s correlation. All experiments were performed in triplicate, and data are expressed as mean ± standard deviation (SD) (*P < 0.05, **P < 0.01).