title: Characterization of proteins secreted by pancreatic cancer cells with             anticancer drug treatment in vitro.
abstract: Pancreatic cancer is one of the most lethal cancers, with an incidence equaling             mortality. It is a heterogeneous group of neoplasms in which pancreatic ductal             adenocarcinoma is most common. Pancreatic cancer cannot be cured even if detected             early. When treatment is initiated, a suitable method of administration of anticancer             drugs must be chosen. Anticancer drugs kill tumor cells. However, side effects             including initiation are problematic in anticancer drug therapy. Improved methods             for the diagnosis of side effects of pancreatic cancer by using sensitive and             specific tumor markers are highly desirable. Therefore, efficient strategies for             biomarker discovery are urgently needed. Here, we present an approach based on             direct experimental access to proteins released by PANC-1 human pancreatic cancer             cells in vitro. A two-dimensional (2-D) map and catalog of this subproteome, herein             termed the secretome, were established comprising more than 1,000 proteins observed             by '2-D difference in-gel electrophoresis analysis using cyanine dye'. We investigated             22 spots that were 1.20-fold upregulated and 31 spots that were 0.66-fold downregulated             by gemcitabine chloride treatment. Proteins in these spots were identified by             nano-high-performance liquid chromatography electrospray ionization time of flight             mass spectrometry/mass spectrometry. Most secretome constituents were nominally             cellular proteins. By mass spectrometry screening, 14-3-3 protein sigma (14-3-3             σ), protein S100-A8, protein S100-A9, galectin-7, lactotransferrin (lactoferrin,             LF) precursor, serotransferrin (transferrin) precursor, and vitamin D binding             protein precursor were identified. Western blotting confirmed the presence of             14-3-3 σ and LF. We found that upregulation of 14-3-3 σ was associated with apoptosis,             and downregulation of LF was found to suppress tumorigenesis.
authors.affiliation: Medical Research Institute, Kanazawa Medical University, Uchinada, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Takata
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Ishigaki
authors.forename: Takeo
authors.initials: T
authors.lastname: Shimasaki
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Tsuchida
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Motoo
authors.forename: Akio
authors.initials: A
authors.lastname: Hayashi
authors.forename: Naohisa
authors.initials: N
authors.lastname: Tomosugi
mesh_terms: D048948:14-3-3 Proteins / Q000032:analysis; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000378:metabolism; D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism*; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D007781:Lactoferrin / Q000032:analysis; D009363:Neoplasm Proteins / Q000032:analysis* / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D040901:Proteomics; D009418:S100 Proteins / Q000032:analysis; D014168:Transferrin / Q000032:analysis; D000093542:Gemcitabine
chemical_list: D048948:14-3-3 Proteins; D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; C490098:LTF protein, human; D009363:Neoplasm Proteins; D009418:S100 Proteins; D014168:Transferrin; D003841:Deoxycytidine; D007781:Lactoferrin; D000093542:Gemcitabine