Overexpression of cyclase-associated protein 2 in multistage hepatocarcinogenesis.
OBJECTIVE
Hepatocellular carcinoma (HCC) associated with chronic liver disease is known to show an obvious multistage process of tumor progression. We previously identified heat shock protein 70 as a molecular marker of early HCC during investigation of expression profiling in multistage hepatocarcinogenesis. In this report, we examined cyclase-associated protein 2 (CAP2), which is also listed as an up-regulated gene in early HCC.


METHODS
We measured the level of CAP2 mRNA by real-time quantitative PCR. We raised a polyclonal antibody against CAP2 and we confirmed the expression of CAP2 by immunoblotting and immunohistochemistry in HCC cell lines and HCC tissues.


RESULTS
According to real-time quantitative PCR, the level of CAP2 mRNA was up-regulated in early HCC when compared with noncancerous liver tissue, and it was further up-regulated in progressed HCC. We raised a polyclonal antibody against CAP2, which showed a single 53-kDa band of strong intensity in the human HCC cell lines and HCC tissues but only a weak band in the noncancerous liver tissues in Western blot analysis. Immunohistochemical examination of CAP2 revealed its significant overexpression in early HCC when compared with noncancerous and precancerous lesions and in progressed HCC when compared with early HCC.


CONCLUSIONS
Our findings show that CAP2 is up-regulated in HCC when compared with noncancerous and precancerous lesions. This is the first report that proves that CAP2 is up-regulated in human cancers and that this is possibly related to multistage hepatocarcinogenesis.
Shibata
Rie
R
Division of Diagnostic Pathology, Department of Pathology, Keio University School of Medicine, and Pathology Division, National Cancer Center Research Institute, Tokyo, Japan.
Mori
Taisuke
T
Du
Wenlin
W
Chuma
Makoto
M
Gotoh
Masahiro
M
Shimazu
Motohide
M
Ueda
Masakazu
M
Hirohashi
Setsuo
S
Sakamoto
Michiie
M
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D001706:Biopsy; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism
D048868:Adaptor Proteins, Signal Transducing; C484231:CAP2 protein, human; D008565:Membrane Proteins; D012333:RNA, Messenger