The present study aimed to determine the expression of microRNA (miRNA or miR)-186 in tumor tissues and peripheral blood of patients with pancreatic cancer (PC), as well as its mechanism of regulation. A total of 65 patients with PC who underwent surgery between June 2013 and October 2015 were included. In addition, 59 healthy subjects were recruited as controls. Reverse transcription-quantitative polymerase chain reaction was used to measure the expression of mRNA and miRNA. Western blotting and enzyme-linked immunosorbent assay were used to determine protein expression. Bioinformatics was employed for the prediction of the target gene of miR-186, whereas dual luciferase reporter assay was performed to identify whether miR-186 directly bound to YAP1 mRNA. Human pulmonary aortic endothelial cells (HPACs) were transfected with ago-miR-186. YAP1 expression in HPACs was silenced by siRNA. MTT assay was used to evaluate the viability of HPACs. YAP1 mRNA and protein expression levels were elevated in PC. In addition, expression levels of miR-186 in PC were downregulated. miR-186 regulated the expression of YAP1 by binding with the 3'-untranslated region of YAP1. Elevated expression of miR-186 inhibited the proliferation of HPACs by downregulating the expression of YAP1. Decreased expression of YAP1 by siRNA reduced the viability of HPACs. The present study demonstrates that YAP1 is upregulated in the tumor tissues and blood of PC patients, and this may be associated with the downregulation of miR-186. In addition, miR-186 may affect the occurrence and development of PC by controlling the proliferation of PC cells via YAP1.
Keywords: microRNA-186; pancreatic cancer; yes-associated protein 1.