[Clinical significance of exosomal miR-1231 in pancreatic cancer].

Objective: To investigate the expression and clinical significance of exosomal miR-1231 in plasma of pancreatic cancer (PC) patients and pancreatic cancer cells. Methods: A total of 16 patients who were diagnosed with pancreatic cancer in Hunan Cancer Hospital were collected from April 2016 to August 2017. Meanwhile, 16 healthy volunteers were recruited as the healthy control group at the same period. The plasma exosomes were extracted, and the levels of miR-1231 were detected by qRT-PCR in PC and healthy control groups. Moreover, the clinicopathological significance of exosomal miR-1231 expression was analyzed. Furthermore, the expression of exosomal miR-1231 was detected in several pancreatic cancer cells (MIA PaCa-2, PANC-1, SW1990, AsPC-1 and BxPc-3) and two normal pancreatic epithelial cells (HPDE and human primary pancreatic epithelial cell). Results: qRT-PCR results showed that the expression level of miR-1231 in plasma exosomes of pancreatic cancer patients (1.06±0.46) was significantly lower than that in healthy controls (2.30±0.99; P<0.05). The levels of exosomal miR-1231 in patients with stage Ⅰ-Ⅱ (1.515±0.531), no distant metastasis (1.236±0.461) and no lymph node metastasis (1.337±0.522) were significantly higher than those with stage Ⅲ-Ⅳ (0.848±0.224), distant metastasis (0.757±0.278) and lymph node metastasis (0.838±0.261), respectively (P<0.05 for all). In addition, there were no correlation between exosomal miR-1231 expression and age, sex, smoking history, CA19-9 levels and tumor sites (P>0.05). Furthermore, the expression level of exosomal miR-1231 in pancreatic cancer cell lines (0.142±0.135) was significantly lower than that in normal epithelial cells (1.127±0.179; P<0.05). Conclusions: The downregulation of exosomal miR-1231 in plasma of pancreatic cancer patients and pancreatic cancer cells suggests that it is related to the initiation and development of PC. It may be a new diagnostic and prognostic marker for PC.