MicroRNAs (miRNAs) act as key regulators of gene expression in diverse biological processes and are intimately involved in tumorigenesis. However, the underlying molecular mechanisms of miR-410 in pancreatic cancer remain poorly understood. In this study, we found that miR-410 overexpression suppressed pancreatic cancer cell growth in vitro and in vivo as well as cell invasion and migration. miR-410 also resulted in G1/S cell-cycle arrest. We then showed that angiotensin II type 1 receptor (AGTR1) was a direct target of miR-410, with miR-410 suppressing AGTR1 expression levels. In contrast, inhibition of miR-410 increased the expression of AGTR1. Silencing of AGTR1 inhibited cell growth and invasion, similar to miR-410 overexpression. In addition, we found that the induction of vascular endothelial growth factor and the activation of the ERK signaling pathway by angiotensin II were blocked by miR-410, similar to the angiotensin II inhibitor losartan. miR-410 overexpression inhibited angiogenesis in mice through the repression of CD31 expression. ERK pathway knockdown suppressed pancreatic cancer cell proliferation, invasion, and angiogenesis. Finally, we found that miR-410 was downregulated in pancreatic cancer tissues compared to adjacent nontumor tissues, whereas AGTR1 was upregulated in pancreatic cancer tissues. Pearson correlation analysis showed that miR-410 and AGTR1 were inversely expressed. In conclusion, our data indicate that miR-410 suppresses pancreatic cancer growth, cell invasion, migration, and angiogenesis via the downregulation of AGTR1, acting as a tumor-suppressive miRNA. In addition, our results suggest that miR-410 is a potential diagnostic biomarker and therapeutic target for patients with pancreatic cancer.
Keywords: Angiotensin II Type 1 Receptor (AGTR1); miR-410; microRNA; tumor suppressor.
© 2015 International Union of Biochemistry and Molecular Biology.