Expression of p57kip2 and its clinical relevance in epithelial ovarian tumors.
BACKGROUND
The aim of this study was to elucidate the expression of p57kip2 in a series of benign, borderline and malignant ovarian tumors, to evaluate its relationship with other G1 regulators of the cell cycle and to determine whether p57kip2 expression is associated with progression and prognosis of epithelial ovarian tumors.


METHODS
Immunohistochemical analysis was performed in 103 cases of epithelial ovarian tumors. Twenty-six of the 103 cases were evaluated by Western blot analysis.


RESULTS
The study demonstrated that high p57kip2 expression was detected in 63.6% (21 out of 33) of benign tumors, 52.2% (12 out of 23) of borderline tumors and 40.4% (19 out of 47) of ovarian carcinomas. The positive ratio of p57kip2 expression was decreased from benign to borderline to malignant tumors, whilst statistical significance was observed between benign and malignant tumors. Low p57kip2 expression was significantly associated with high tumor grades, advanced clinical stages and cyclin E overexpression. Kaplan-Meier analysis demonstrated that the patients with low p57kip2 expression had a short overall survival. When the combined phenotype of p57kip2 and p27kip1 was analyzed, the patients with both p57kip2 and p27kip1 low expression had a lower overall survival rate.


CONCLUSIONS
These findings suggest that decreased p57kip2 expression may play a pivotal role in the progression of ovarian tumors and provide an important prognostic implication for epithelial ovarian carcinomas.
Sui
Li
L
Department of Physiology, Kagawa Medical University, 1750-1 Ikenobe, Miki-Cho, Kida-Gun, Kagawa, 761-0793, Japan.
Dong
Youyi
Y
Ohno
Masayuki
M
Watanabe
Yasuo
Y
Sugimoto
Katsuyoshi
K
Tokuda
Masaaki
M
D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000096:biosynthesis; D050761:Cyclin-Dependent Kinase Inhibitor p57; D018450:Disease Progression; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009367:Neoplasm Staging; D009687:Nuclear Proteins / Q000096:biosynthesis*; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate
C493964:CDKN1C protein, human; D018797:Cell Cycle Proteins; D050761:Cyclin-Dependent Kinase Inhibitor p57; D009687:Nuclear Proteins