Analysis of serum exosomal microRNAs and clinicopathologic features of patients with pancreatic adenocarcinoma

Abstract

BackgroundAltered expression of serum microRNAs (miRNAs) have been reported to correlate with carcinogenesis and progression of pancreatic adenocarcinoma (PC), but descriptions of serum exosomal miRNAs in PC are still lacking. This study was designed to evaluate serum exosomal miRNA levels in PC patients and to investigate their relationships with clinicopathologic features and prognosis.MethodsFour miRNAs (miR-17-5p, miR-21, miR-155 and miR-196a) related to PC were selected for examination in our research. Serum miRNA was examined by RT-PCR in a group of 49 patients, including 22 with PCs, 6 with benign pancreatic tumors, 7 with ampullary carcinomas, 6 with chronic pancreatitis and 8 healthy participants. The clinicopathologic data were also collected, and PC patients were classified according to the presence of metastasis, tumor differentiation and advanced stage.ResultsThere were low expressions of exosomal miR-155 and miR-196a in serum samples of PC patients when U-6 was used as a control. Serum exosomal miR-17-5p was higher in PC patients than in non–PC patients and healthy participants. High levels of miR-17-5p were significantly correlated with metastasis and advanced stage of PC. The serum exosomal miR-21 level in PC was higher than that in the normal and chronic pancreatitis groups, but was not significantly correlated with PC differentiation and tumor stage.ConclusionsThere were high expressions of serum exosomal miR-17-5p and miR-21 in PC patients. Examination of serum exosomal microRNA is a useful serum biomarker for PC diagnosis other than serum-free microRNA. It is postulated that exosomal miR-17-5p participates in the progression of PC.

Exosome-shuttling microRNA-21 promotes cell migration and invasion-targeting PDCD4 in esophageal cancer

“…Ogata-Kawata et al (53) found that the amount of seven serum exosomal miRNAs (i.e., let-7a, miR-1229, miR-1246, miR-150, miR-21, miR-223 and miR-23a) from the serum of TNM stage I colorectal cancer patients were significantly higher than in healthy controls; this finding suggested that serum exosomal miRNAs may serve as significant biomarkers for the early detection of primary colorectal cancer (53). One study of pancreatic adenocarcinoma (PC) found that serum exosomal miR-17-5p and miR-21 were significantly elevated in the advanced stage and metastatic PC patients; moreover, the diagnostic sensitivity and specificity were 72.7 and 92.6% for miR-17-5p and 95.5 and 81.5% for miR-21, respectively (54). In the present study, microarray analysis of plasma from esophageal cancer patients and healthy controls identified 20 miRNAs that could distinguish the plasma from ESCC patients and healthy controls.…”

Versatile roles of extracellular vesicles in cancer

“…Importantly, miRNAs can be readily detected in small-volume samples using specific and sensitive quantitative real-time PCR (qRT-PCR) (68). Additionally, EV-associated miRNAs have been used as diagnostic and prognostic markers (20,(69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79). Microarray analyses of miRNAs in EV-enriched fractions of serum from 88 patients with primary colorectal cancer (CRC) and 11 healthy controls revealed that that the levels of 7 miRNAs were significantly higher in the serum EVs of CRC patients compared with serum EVs from healthy donors (74).…”

Exosome‑mediated peritoneal dissemination in gastric cancer and its clinical applications (Review)

“…Serum exosomal miR-17-5p and miR-21 were highly expressed in pancreatic adenocarcinoma patients (46). Ren et al (47) analyzed gastric cancer-derived exosomes by next-generation sequencing technology, and demonstrated that these exosomes contained more proteins and RNAs than normal gastric mucosal epithelial cell-derived exosomes, with miRNA-21-5p and miRNA-30a-5p having the most abundant miRNA profiles.…”