Pfetin as a prognostic biomarker in gastrointestinal stromal tumor: novel monoclonal antibody and external validation study in multiple clinical facilities.
OBJECTIVE
The clinical course of gastrointestinal stromal tumor (GIST) spans a wide spectrum from a curable disorder to a highly malignant disease that leads to metastasis and death. To develop prognostic modalities for GIST patients, we developed a mouse monoclonal antibody against pfetin, the prognostic value of which has been previously reported.


METHODS
The reactivity of the monoclonal antibody against pfetin was examined by western blotting and immunohistochemistry.


RESULTS
Western blotting demonstrated that the monoclonal antibody was specific to pfetin. The immunohistochemical study demonstrated that the 5-year disease-free survival rate was 93.2% and 94.5% for GIST patients with pfetin-positive tumors and 70.0% and 80.7% for those with pfetin-negative tumors in the 159 cases from the National Cancer Center Hospital (P < 0.0001) and in the 100 cases from Niigata University Medical and Dental Hospital (P < 0.0001), respectively. Uni- and multivariate analyses revealed that pfetin expression was a powerful prognostic factor among the clinico-pathological parameters examined.


CONCLUSIONS
These results establish pfetin as a practical prognostic marker for GIST patients after surgery. Pfetin may also present a novel therapeutic target to prevent recurrence of GIST.
Kikuta
Kazutaka
K
Proteome Bioinformatics Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
Gotoh
Masahiro
M
Kanda
Tatsuo
T
Tochigi
Naobumi
N
Shimoda
Tadakazu
T
Hasegawa
Tadashi
T
Katai
Hitoshi
H
Shimada
Yasuhiro
Y
Suehara
Yoshiyuki
Y
Kawai
Akira
A
Hirohashi
Setsuo
S
Kondo
Tadashi
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000097:blood* / Q000737:chemistry / Q000276:immunology; D015153:Blotting, Western; D045744:Cell Line, Tumor; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011506:Proteins / Q000032:analysis* / Q000737:chemistry / Q000235:genetics
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; C493175:KCTD12 protein, human; D011506:Proteins