Pancreatic
cystic neoplasms represent 10-15% of primary cystic masses of the pancreas. While
pancreatic cysts are detected with an increasing frequency due to the use of advanced imaging modalities in clinical practice, the diagnosis of pancreatic
cystic neoplasms remains unsatisfactory because available diagnostic techniques proved not sensitive enough so far. This study was designed to characterize the proteomic pattern of
pancreatic cyst fluids obtained from various cystic lesions. Cyst fluids were collected by direct
puncture during open surgery to avoid any possible contamination from other tissues. CEA, CA-19-9, and
amylase concentrations were measured using specific immunoassays. After immunodepletion and fractionation by SDS-PAGE,
proteins were digested and analyzed by LC-MS/MS. Specific histological lesions were found to be associated with distinct
protein patterns. Interestingly, some of these
proteins have been proposed as
biomarkers of
pancreatic cancer. Immunoblots allowed for verifying the differential expression in specific cyst fluids of two selected
proteins, olfactomedin-4 and mucin-18. Finally, immunohistochemistry was performed to correlate these data with the expression pattern of olfactomedin-4 and mucin-18 in
pancreatic cyst tissues. Results from this study indicate that proteomic analysis of cyst fluid could provide reliable candidates for developing new
biomarkers for the preoperative management of malignant and premalignant
pancreatic cysts.