Enhanced expression of cyclin E and cyclin A in human hepatocellular carcinomas.
BACKGROUND
Disruption of the G1/S check point leads to uncontrolled cell growth, resulting in the development of cancers.


METHODS
Cell cycle regulatory molecules were investigated in 33 surgically resected hepatocellular carcinoma (HCC) samples from 30 patients by Western blotting.


RESULTS
Enhanced expressions of cyclin E and cyclin A were detected at frequencies of 18/33 and 26/33 in HCCs, respectively, as compared with their neighboring noncancerous tissues. The enhanced expression of cyclin E, but not that of cyclin A, correlated with hyperphosphorylation of pRb and high frequency of Ki-67-positive cells. Thus, the HCCs with enhanced cyclin E expression probably contain a relatively large number of proliferating cancer cells.


CONCLUSIONS
The degree of cyclin E expression can be used as a prognostic parameter of HCC. In addition, cyclin E may become a molecular target in the treatment of HCCs.
Ohashi
R
R
Department of Cell Biology, Institute of Cellular and Molecular Biology, Okayama University Medical School, 2-5-1 Shikata, Okayama 700-8558, Japan.
Gao
C
C
Miyazaki
M
M
Hamazaki
K
K
Tsuji
T
T
Inoue
Y
Y
Uemura
T
T
Hirai
R
R
Shimizu
N
N
Namba
M
M
D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins; D019925:Cyclin A / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D019927:Cyclin E / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000032:analysis; D005260:Female; D016193:G1 Phase; D015972:Gene Expression Regulation, Neoplastic; D016158:Genes, p53; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis; D008113:Liver Neoplasms / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008297:Male; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D016160:Retinoblastoma Protein / Q000737:chemistry; D025521:Tumor Suppressor Proteins
C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D019925:Cyclin A; D019927:Cyclin E; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D019394:Ki-67 Antigen; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D016160:Retinoblastoma Protein; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27