Mass spectrometry-based proteomic analysis of formalin-fixed paraffin-embedded extrahepatic cholangiocarcinoma.
BACKGROUND
Extrahepatic cholangiocarcinoma is very difficult to diagnose at an early stage, and has a poor prognosis. Novel markers for diagnosis and optimal treatment selection are needed. However, there has been very limited data on the proteome profile of extrahepatic cholangiocarcinoma. This study was designed to unravel the proteome profile of this disease and to identify overexpressed proteins using mass spectrometry-based proteomic approaches.


METHODS
We analyzed a discovery set of formalin-fixed paraffin-embedded tissues of 14 extrahepatic cholangiocarcinomas using shotgun mass spectrometry, and compared proteome profiles with those of seven controls. Then, selected candidates were verified by quantitative analysis using scheduled selected reaction monitoring-based mass spectrometry. Furthermore, immunohistochemical staining used a validation set of 165 cases.


RESULTS
In total, 1,992 proteins were identified and 136 proteins were overexpressed. Verification of 58 selected proteins by quantitative analysis revealed 11 overexpressed proteins. Immunohistochemical validation for 10 proteins showed positive rates of S100P (84%), CEAM5 (75%), MUC5A (62%), OLFM4 (60%), OAT (42%), CAD17 (41%), FABPL (38%), AOFA (30%), K1C20 (25%) and CPSM (22%) in extrahepatic cholangiocarcinomas, which were rarely positive in controls.


CONCLUSIONS
We identified 10 proteins associated with extrahepatic cholangiocarcinoma using proteomic approaches. These proteins are potential targets for future diagnostic biomarkers and therapy.
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.|Department of Surgery, South Miyagi Medical Center, Miyagi, Japan.
Shimpei
S
Maeda
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
Takanori
T
Morikawa
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
Tatsuyuki
T
Takadate
Department of Pathology and Histotechnology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Takashi
T
Suzuki
Nanotechnology Innovation Station, National Institute for Materials Science, Tsukuba, Japan.
Takashi
T
Minowa
Nanotechnology Innovation Station, National Institute for Materials Science, Tsukuba, Japan.
Nobutaka
N
Hanagata
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
Tohru
T
Onogawa
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
Fuyuhiko
F
Motoi
Department of Surgery I, Tokyo Medical University, Tokyo, Japan.
Toshihide
T
Nishimura
Department of Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
Michiaki
M
Unno
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000737:chemistry* / Q000473:pathology; D017734:Bile Ducts, Extrahepatic; D014408:Biomarkers, Tumor / Q000032:analysis; D018281:Cholangiocarcinoma / Q000737:chemistry* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008875:Middle Aged; D040901:Proteomics / Q000379:methods*; D012189:Retrospective Studies; D016707:Tissue Fixation / Q000379:methods; D055815:Young Adult
D014408:Biomarkers, Tumor
Biomarker; Extrahepatic cholangiocarcinoma; Mass spectrometry; Proteomics; Scheduled selected reaction monitoring