Fig. 6.

MYH9 is a direct target of miR-449b-5p. a Clustered heatmap of the differentially expressed mRNAs in PDAC tissues from five T4 PDAC patients with long survival time and tissues from five T4 PDAC patients with short survival time. b Venn diagram shows the overlap of the target mRNAs of miR-449b-5p predicted by miRDB, miWalk and the results of RNA-seq. c Table of target mRNAs selected for miR-449b-5p. d A schematic of the wild-type (WT) and mutant (MUT) COL12A1 or MYH9 luciferase reporter vectors. e-f A luciferase reporter assay was used to confirm the interaction between COL12A1 and miR-449b-5p. g-h A luciferase reporter assay was used to confirm the interaction between MYH9 and miR-449b-5p. i-l The expression levels of COL12A1 and MYH9 in PDAC tissues and matched noncancerous tissues were detected by qRT–PCR. Kaplan–Meier analyses were used to illuminate the correlation between the levels of COL12A1 and MYH9 and the survival time of PDAC patients. The median expression value of COL12A1 and MYH9 was used as the cutoff (n = 49). Log-rank tests were used to determine the statistical significance. m-n Representative COL12A1 and MYH9 IHC images of a tissue microarray containing 97 pairs of PDAC and corresponding noncancerous pancreatic tissues. Original magnification 75× and 300×. Scale bar = 100 μm. The protein levels of COL12A1 and MYH9 were significantly increased in PDAC tissues. o-p The expression levels of MYH9 mRNA (o) and protein (p) were significantly downregulated in PDAC cells transfected with miR-449b-5p mimics and upregulated in PDAC cells transfected with miR-449b-5p inhibitor. (Values are expressed as the means ± SDs; *P < 0.05, **P < 0.01 and ***P < 0.001)