Overexpression of tyrosine kinase B protein as a predictor for distant metastases and prognosis in gastric carcinoma.
OBJECTIVE
Tyrosine kinase B (TrkB) is associated with aggressive behavior and poor prognosis in various cancers. Here we examined the association between TrkB expression and distant metastases/prognosis in gastric carcinoma (GC).


METHODS
We analyzed TrkB expression in 161 GC patients by immunohistochemistry and Western blot analysis. The correlation of TrkB mRNA and protein expression levels was examined in 10 patients by RT-PCR assay.


RESULTS
TrkB expression was of level 1 in 97 (60.2%) and level 2 in 64 (39.8%) patients. Patients with level 2 expression had a significantly higher incidence of distant metastases (p < 0.0001), well-differentiated tumors (p < 0.005), deeper depth of invasion (p < 0.005) and poorer disease-free and overall survival (p < 0.0001 each) compared to patients with level 1. Multivariate analysis identified the level of TrkB expression as an independent prognostic factor for both disease-free and overall survival (p < 0.01 and p < 0.0001, respectively). Both lymph node metastasis (odds ratio = 10.7) and TrkB expression (odds ratio = 9.3) were independent predictors of distant metastases.


CONCLUSIONS
A high level of TrkB expression was observed in well-differentiated GC subtypes and is a predictor for distant metastases and prognosis in GC.
Zhang
Yong
Y
Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
Fujiwara
Yoshiyuki
Y
Doki
Yuichiro
Y
Takiguchi
Shuji
S
Yasuda
Takushi
T
Miyata
Hiroshi
H
Yamazaki
Makoto
M
Ngan
Chew Yee
CY
Yamamoto
Hirofumi
H
Ma
Qingyong
Q
Monden
Morito
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000556:secondary; D016019:Survival Analysis
D011505:Protein-Tyrosine Kinases