title: Secretome-based identification of ULBP2 as a novel serum marker for pancreatic cancer detection.
abstract: BACKGROUND
  To discover novel markers for improving the efficacy of pancreatic cancer (PC) diagnosis, the secretome of two PC cell lines (BxPC-3 and MIA PaCa-2) was profiled. UL16 binding protein 2 (ULBP2), one of the proteins identified in the PC cell secretome, was selected for evaluation as a biomarker for PC detection because its mRNA level was also found to be significantly elevated in PC tissues.
  
  
  METHODS
  ULBP2 expression in PC tissues from 67 patients was studied by immunohistochemistry. ULBP2 serum levels in 154 PC patients and 142 healthy controls were measured by bead-based immunoassay, and the efficacy of serum ULBP2 for PC detection was compared with the widely used serological PC marker carbohydrate antigen 19-9 (CA 19-9).
  
  
  RESULTS
  Immunohistochemical analyses revealed an elevated expression of ULPB2 in PC tissues compared with adjacent non-cancerous tissues. Meanwhile, the serum levels of ULBP2 among all PC patients (n = 154) and in early-stage cancer patients were significantly higher than those in healthy controls (p<0.0001). The combination of ULBP2 and CA 19-9 outperformed each marker alone in distinguishing PC patients from healthy individuals. Importantly, an analysis of the area under receiver operating characteristic curves showed that ULBP2 was superior to CA 19-9 in discriminating patients with early-stage PC from healthy controls.
  
  
  CONCLUSIONS
  Collectively, our results indicate that ULBP2 may represent a novel and useful serum biomarker for pancreatic cancer primary screening.
authors.affiliation: Graduate Institute of Biomedical Sciences, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Chang
authors.forename: Chih-Ching
authors.initials: CC
authors.lastname: Wu
authors.forename: Yi-Ming
authors.initials: YM
authors.lastname: Shyr
authors.forename: Tse-Ching
authors.initials: TC
authors.lastname: Chen
authors.forename: Tsann-Long
authors.initials: TL
authors.lastname: Hwang
authors.forename: Ta-Sen
authors.initials: TS
authors.lastname: Yeh
authors.forename: Kai-Ping
authors.initials: KP
authors.lastname: Chang
authors.forename: Hao-Ping
authors.initials: HP
authors.lastname: Liu
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Liu
authors.forename: Ming-Hung
authors.initials: MH
authors.lastname: Tsai
authors.forename: Yu-Sun
authors.initials: YS
authors.lastname: Chang
authors.forename: Jau-Song
authors.initials: JS
authors.lastname: Yu
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000097:blood; D058851:GPI-Linked Proteins / Q000097:blood; D020869:Gene Expression Profiling; D006801:Humans; D007118:Immunoassay; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000097:blood; D000099222:betaIG-H3 Protein
chemical_list: D014408:Biomarkers, Tumor; D016326:Extracellular Matrix Proteins; D058851:GPI-Linked Proteins; D036341:Intercellular Signaling Peptides and Proteins; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein; C423230:ULBP2 protein, human