Focal adhesion kinase is overexpressed in hepatocellular carcinoma and can be served as an independent prognostic factor.
OBJECTIVE
The development of human malignancies can be attributed to aberrant regulation of intracellular signal transduction pathways. In the current study, we aimed to evaluate focal adhesion kinase (FAK), a non-receptor tyrosine kinase, expression in hepatocellular carcinoma (HCC), and to explore the prognostic significance of FAK.


METHODS
We investigated FAK mRNA expression in 60 HCC specimens using quantitative real-time reverse transcription polymerase chain reaction analysis, and the correlation between FAK expression and clinicopathologic parameters. FAK protein expression was examined using Western blot analysis and an immunohistochemical study.


RESULTS
We found that FAK mRNA was overexpressed in HCCs compared with the corresponding non-cancerous liver tissues (P=0.0008). The FAK overexpression correlated significantly with tumor size (P=0.034) and serum AFP level (P=0.030). Univariate and multivariate analyses revealed that FAK mRNA expression was an independent prognostic factor for disease-free (risk ratio 3.83; P=0.024) and overall (risk ratio 7.14; P=0.015) survival. Besides, we confirmed immunohistochemically that the FAK protein was detectable in cancer cells despite non-expression in corresponding non-cancerous tissues.


CONCLUSIONS
Our results suggest that FAK mRNA expression has prognostic significance for the survival of patients with HCC.
Fujii
Tsutomu
T
Department of Surgery II, Graduate School and Faculty of Medicine, University of Nagoya, 65 Tsuruma-cho, Showa-ku, Nagoya 466-8550, Japan.
Koshikawa
Katsumi
K
Nomoto
Shuji
S
Okochi
Osamu
O
Kaneko
Tetsuya
T
Inoue
Soichiro
S
Yatabe
Yasushi
Y
Takeda
Shin
S
Nakao
Akimasa
A
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000401:mortality / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496050:PTK2 protein, human