Identification of a Specific Vimentin Isoform That Induces an Antibody Response in Pancreatic Cancer.
Pancreatic cancer has a poor prognosis, in part due to lack of early detection. The identification of circulating tumor antigens or their related autoantibodies provides a means for early cancer diagnosis. We have used a proteomic approach to identify proteins that commonly induce a humoral response in pancreatic cancer. Proteins from a pancreatic adenocarcinoma cell line (Panc-1) were subjected to two-dimensional PAGE, followed by Western blot analysis in which individual sera were tested for autoantibodies. Sera from 36 newly diagnosed patients with pancreatic cancer, 18 patients with chronic pancreatitis and 15 healthy subjects were analyzed. Autoantibodies were detected against a protein identified by mass spectrometry as vimentin, in sera from 16/36 patients with pancreatic cancer (44.4%). Only one of 18 chronic pancreatitis patients and none of the healthy controls exhibited reactivity against this vimentin isoform. Interestingly, none of several other isoforms of vimentin detectable in 2-D gels exhibited reactivity with patient sera. Vimentin protein expression levels were investigated by comparing the integrated intensity of spots visualized in 2-D PAGE gels of various cancers. Pancreatic tumor tissues showed greater than a 3-fold higher expression of total vimentin protein than did the lung, colon, and ovarian tumors that were analyzed. The specific antigenic isoform was found at 5-10 fold higher levels. The detection of autoantibodies to this specific isoform of vimentin may have utility for the early diagnosis of pancreatic cancer.
Hong
Su-Hyung
SH
Departments of Pediatrics (SHH, DEM, HW, EP, RH, SMH), Pathology (TJG and JKG), Physiology (CDL), Surgery (DMS) and Internal Medicine (DEB), University of Michigan Medical School, 1150 W. Medical Center Drive, Ann Arbor, Michigan 48109 and the Department of Dental Microbiology (SHH), School of Dentistry, Kyungpook National University, 101 Dongin-Dong, Jung-Gu, Daegu, 700-422, South Korea.
Misek
David E
DE
Wang
Hong
H
Puravs
Eric
E
Hinderer
Robert
R
Giordano
Thomas J
TJ
Greenson
Joel K
JK
Brenner
Dean E
DE
Simeone
Diane M
DM
Logsdon
Craig D
CD
Hanash
Samir M
SM