br To further predict the miRNA regulating ADAM
To further predict the miRNA regulating ADAM9, five miRNA-mRNA relation prediction databases (TargetScan, miRSearch, miRTarBase, miRWalk, and mirDIP) were used to predict the target miRNA, after which the results obtained were compared with the
predicted results. The detailed results are displayed in Table S2. In accordance with the Venn diagram (Figure 1H), three intersection miRNAs, hsa-miR-26b-5p, hsa-miR-126-3p, and hsa-miR-373-3p, were found by comparison of five miRNA prediction results, indi-cating that these three miRNAs were highly likely to regulate ADAM9. Furthermore, through screening of the miRNA MitoPY1 chip GEO: GSE28955 of pancreatic cancer by R, among the three aforementioned miRNAs that targeted ADAM9, only hsa-miR-126-3p was poorly expressed in pancreatic cancer tissues (Figure 1I), suggesting that miR-126 could target ADAM9 in pancreatic cancer. The specific expression data of ADAM9 and hsa-miR-126 are de-picted in Table S3.
miR-126-3p Is Poorly Expressed in Pancreatic Cancer Cells
In order to ascertain whether the expression of miR-126-3p is altered in pancreatic cancer cells, its expression in 28 patients with pancreatic cancer, as well as among 32 patients with pancreatitis, was determined through the application of qRT-PCR. The expression of miR-126-3p in the pancreatic cancer tissues was markedly lower than the results of the patients with pancreatitis (Figure 2A), suggesting that miR-126-3p is downregulated in pancreatic cancer cells. In addition, qRT-PCR was employed to detect the expression of miR-126-3p in the normal human pancreatic cell line HPC-Y5, with six pancreatic can-cer cell lines (PANC-1, SW1990, Capan-1, AsPC-1, PC-3, and MIAPaCa-2 cell lines) screened in order to detect the cell line with the poorest expression of miR-126-3p. The results obtained distinctly indicated that the expression of miR-126-3p was decreased among all the pancreatic cancer cell lines when compared with the normal pancreatic cell line HPC-Y5 (Figure 2B), with the expression of miR-126-3p in PANC-1 found to be the lowest (p < 0.05) among all tested pancreatic cancer cell lines. Thus, PANC-1 was selected for subsequent cell experiments.
miR-126-3p Inhibits Proliferation, Migration, and Invasion of Pancreatic Cancer Cells and Promotes Their Apoptosis
In order to examine the influence of miR-126-3p on pancreatic cancer cells, PANC-1 was treated with a mimic and inhibitor of miR-126-3p. The results (Figures 3A–3D) revealed that when compared with the mimic-negative control (NC) group, the cell proliferation, migration, and invasion abilities were decreased, whereas the apoptotic rate was elevated in the miR-126-3p mimic group (p < 0.05). In contrast, when compared with the inhibitor-NC group, the miR-126-3p inhibitor group exhibited increased cell proliferation, migration, and invasion abilities along with a diminished rate of apoptosis (p < 0.05). Restored miR-126-3p was associated with inhibited proliferation, migration, and invasion of pancreatic cancer cells in addition to stimulated rates of apoptosis, whereas a contradictory trend was observed when miR-126-3p was silenced and opposite outcomes to the above mentioned were exhibited.
Based on the online software analysis, miR-126-3p was detected to have a specific binding region for ADAM9 within its 30 UTR (Fig-ure 4A). In order to ascertain as to whether miR-126-3p regulates
G Overall Survival 1.0
Low ADAM9 TPM
High ADAM9 TPM
type 14 type C
type 14 type
C12orf39 tumor TWIST2 12 tumor
PEX5L FGD6 6