Fig 2: EIF5A2 is a target of miR-218-5p. a The binding sites of miR-218-5p on EIF5A2. b, c Dual-luciferase reporter assay in Huh7/DOX and HCCLM3/DOX cells co-transfected with the reporter plasmid and the indicated miRNAs. d-i mRNA and protein levels analysis of EIF5A2 in HCC tissues, DOX-resistant tissues and matched normal tissues (d, e), normal hepatocyte THLE-2 and HCC cell lines (Hep3B, Huh7 and HCCLM3) (f, g), as well as DOX-resistant HCC cell lines and parental HCC cells (h, i) using qRT-PCR and western blot. j Correlation analysis between EIF5A2 and miR-218-5p expression. k, l Levels analysis of EIF5A2 expression in Huh7/DOX and HCCLM3/DOX cells transfected with miR-NC or miR-218-5p using qRT-PCR and western blot. *P < 0.05

Fig 3: Circ_0003998 serves as a ceRNA for miR-218-5p to regulate EIF5A2 expression. a, b Western blot analysis of EIF5A2 expression in Huh7/DOX and HCCLM3/DOX cells transfected with si-NC, si-circ_0003998, si-circ_0003998 + anti-miR-NC, or si-circ_0003998 + anti-miR-218-5p. c Correlation analysis between EIF5A2 and circ_0003998 expression. *P < 0.05

Fig 4: EIF5A2 reversed the effects of miR-9 on cell viability. (A) Western blot confirmation of EIF5A2 siRNA interference efficiency in Hep3B and SNU449 cells. (B, C) CCK-8 assay of Hep3B cells (B) and SNU449 cells (C) transfected with EIF5A2 siRNA plus synthetic miR-9 inhibitor or control in the presence of cisplatin (0, 1.5, 3.0, 4.5 μg/ml).

Fig 5: miR-9 and EIF5A2 regulated the EMT pathway. (A) Western blot comparison of E-cadherin and vimentin protein expression levels between HCC cells transfected with miR-9 mimic or miR-9 inhibitor. (B) Western blot comparison of E-cadherin and vimentin protein expression levels between HCC cells transfected with EIF5A2 siRNA or control siRNA. (C) E-cadherin and vimentin protein expression levels in Hep3B and SNU449 cells transfected with EIF5A2 siRNA alone or EIF5A2 siRNA plus miR-9 inhibitor. GAPDH was the internal control.