Size and Concentration of Extracellular Vesicles in Pancreatic Juice From Patients With Pancreatic Ductal Adenocarcinoma

Extracellular vesicles (EVs) and their cargo may provide promising biomarkers for the early detection of pancreatic ductal adenocarcinoma (PDAC). Although blood-borne EVs are most frequently studied as cancer biomarkers, pancreatic juice (PJ) may represent a better biomarker source because it is in close contact with the ductal cells from which PDAC arises. It is, as yet, unknown whether PDAC results in a distinct type or increased number of particles in PJ and whether this has diagnostic value. METHODS: Secretin-stimulated PJ was collected from the duodenum of 54 cases and 117 nonmalignant controls under surveillance for PDAC. Serum was available for a subset of these individuals. The vesicular composition of these biofluids was analyzed with nanoparticle tracking analysis. RESULTS: The concentration of EVs did not differ between controls and PDAC cases. However, a higher number of large vesicles were found in PJ (but not serum) for patients with PDAC compared with controls. DISCUSSION: The composition of isolated EVs from PJ, but not serum, is altered in patients with PDAC. This suggests that PJ may carry disease-specific markers not present in serum and provides a valuable biomarker source for PDAC diagnosis. The nature of the larger particles in EV isolates from PJ of PDAC cases requires further investigation.