PDCD4 is the downstream target gene of miR-21-5p. A. We used miRWalk and TargetScan to search for the related target genes of miR-21-5p. The MiR-NC/miR-21-5p mimics and the NC-inhibitor/miR-21-5p inhibitor were transfected in the LPS-treated H9c2 cells, and we used qRT-PCR to test the levels of the 14 intersection target genes. Values are mean ± sd, **P<0.01 vs. miR-NC or NC-inhibitor, n=3 per group. B. The predicted binding sites of PDCD4 and miR-21-5p. C. Luciferase reporter assays were performed to analyze the interaction of WT or MUT PDCD4 3’-UTR with miR-21-5p. The values are the mean ± sd, **P<0.01 vs. the NC mimics, n=3 per group. D. The NC-inhibitor and the miR-21-5p inhibitor were transfected in the H9c2 cells. The expression of PDCD4 was analyzed using qRT-PCR. E. We used Western blot to determine the expressions of PDCD4. The values are the mean ± sd, **P<0.01 vs. NC-inhibitor, n=3 per group.