Circular RNA circVAPA promotes chemotherapy drug resistance in gastric cancer progression by regulating miR-125b-5p/STAT3 axis

Figure 5 MiR-125b-5p targets STAT3 in gastric cancer cells. A: The binding of miR-125b-5p and the 3’ untranslated region of STAT3 was identified by bioinformatic analysis based on Targetscan (http://www.targetscan.org/vert_72/); B-D: SGC7901 and HGC27 cells were treated with control mimic or miR-125b-5p mimic. The luciferase activities of wild type STAT3 and STAT3 with the miR-125b-5p-binding site mutant were examined by luciferase reporter gene assay (B), the mRNA expression of STAT3 was analyzed by qPCR assay (C), and the protein expression of STAT3 was determined by Western blot analysis (D); E: SGC7901 and HGC27 cells were treated with control shRNA or circVAPA shRNA, or co-treated with circVAPA shRNA and miR-125b-5p inhibitor. The protein expression of STAT3 was tested by Western blot analysis. Data are presented as the mean ± SD. ^bP < 0.01. MUT: Mutant; WT: Wild type.