Integrative Preoteomic Analysis of Cell Line Conditioned Media and Pancreatic Juice for the Identification of Candidate Pancreatic Cancer Biomarkers

Novel serological biomarkers to aid in the detection and clinical management of pancreatic cancer patients are urgently needed. In the present study, we performed in-depth proteomic analysis of conditioned media from six pancreatic cancer cell lines (MIA-PaCa2, PANC1, BxPc3, CAPAN1, CFPAC1 and SU.86.86), the normal pancreatic ductal epithelial cell line HPDE, and pancreatic juice samples from cancer patients for identification of novel biomarker candidates. Using 2D-LC-MS/MS, a total of 3479 non-redundant proteins were identified with ≥2 peptides. Subsequent label-free protein quantification and integrative analysis of the biological fluids resulted in the generation of candidate biomarkers, of which five proteins were shown to be significantly elevated in plasma from pancreatic cancer patients in a preliminary assessment. Further verification of two of the proteins in ~200 serum samples demonstrated the ability of these proteins to significantly improve the area under the receiver operating characteristic curve of CA19.9 from 0.84 to 0.91.MAS