Analysis of Extracellular Vesicles and Clinical Application in Pancreatic Cancer.

Background/Aims Recent studies highlight the putative utility of tissue-specific vesicles in diagnosis and disease monitoring in pancreatic cancer. Exosomes are small extracellular vesicles released via the endocytic pathway by fusion of multivesicular bodies with the plasma membrane. Because exosomes contain an abundant of cell-specific biomolecules acting as a fingerprint of the cell of origin, they possess promising potential as novel biomarkers for early cancer detection. Therefore, we examined exosome-derived proteins and RNAs in liquid biopsies of patients with pancreatic ductal adenocarcinoma (PDAC). Methods For our study, 100 PDAC and 23 benign patients were enrolled to collect blood samples. A lab-on-a-disc "Exodisc" based on a centrifugal microfluidic filter system was used for the automatic enrichment and isolation of exosomes from plasma along with subsequent analysis by in situ enzyme-linked immunosorbent assay or fluorescence labeling for putative protein markers; CD9, CD63, CD81, GPC1, Caveolin1, Alix, Flot1, epidermal growth factor receptor, epithelial cell adhesion molecule (EpCAM). Clinical and laboratory data was reviewed. AI technique was applied to find out correlation between exosome analysis results and clinical parameters. Results The total of 100 patients with PDACs were enrolled as study patients. The median overall survival (OS) of study patients was 13.9 months. The clinical staging were the following: II (A,B), 12; III, 33; IV, 55. The first line chemotherapy regimen of study patients was Gemcitabine/Abraxane or FOLFIRNOX. Nine protein markers were examined with isolated exosomes from the patient plasma. PDAC patients were divided by two groups with good prognosis (OS ≥36 months) and poor prognosis (OS <36 months) after chemotherapy. As a result, the level of exosomal GPC1, CD63 and EpCAM was increased in the poor prognosis group. Conclusions We found some candidates of exosomal protein markers predicting chemotherapy response and prognosis. This is the first study investigating correlation between clinicopathology of PDACs and exosome markers via AI technique. [ABSTRACT FROM AUTHOR]