Expression of estrogen-responsive finger protein (Efp) is associated with advanced disease in human epithelial ovarian cancer.
OBJECTIVE
The estrogen-responsive ring finger protein (Efp) gene, one of estrogen receptor (ER) target genes, is considered to be essential for estrogen-dependent cell proliferation. To understand the estrogenic action on ovarian cancer, we studied the relationships between Efp and ERs expressions and the correlations of Efp expression with clinicopathological parameters in epithelial ovarian cancer.


METHODS
The protein expressions for Efp, ERalpha and ERbeta were examined by immunoblotting in 12 ovarian cancer cell lines. Efp mRNA expressions were evaluated by quantitative RT-PCR in 12 ovarian cancer cell lines. A total of 100 surgical specimens diagnosed as epithelial ovarian cancer were examined immunohistochemically using antibodies for Efp, ERalpha and ERbeta.


RESULTS
Efp protein was detected in 8 out of 12 cell lines. In Efp protein-positive cell lines, Efp mRNA was expressed higher than that in negative (P=0.021). All of the Efp protein-positive cell lines simultaneously expressed either ERalpha or ERbeta protein. By immunohistochemical staining, Efp immunoreactivity was detected in 63 out of 100 ovarian cancer specimens and positive signals were in the cytoplasm of carcinoma cells. There were significant correlations between Efp and ERalpha, ERbeta immunoreactivity (Efp and ERalpha, P=0.022; Efp and ERbeta, P=0.032). Efp expression was significantly higher in a subgroup with serous adenocarcinoma (P=0.010) and with advanced disease (P=0.026). No significant relationship was detected between Efp immunoreactivity and overall survival.


CONCLUSIONS
The expression of Efp was detected in human epithelial ovarian cancer and high expression of Efp was correlated with advanced disease and serous adenocarcinoma, and ERs status.
Sakuma
Michiko
M
Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan. msakuma@mail.tains.tohoku.ac.jp
Akahira
Jun-ichi
J
Suzuki
Takashi
T
Inoue
Satoshi
S
Ito
Kiyoshi
K
Moriya
Takuya
T
Sasano
Hironobu
H
Okamura
Kunihiro
K
Yaegashi
Nobuo
N
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D047628:Estrogen Receptor alpha / Q000096:biosynthesis; D047629:Estrogen Receptor beta / Q000096:biosynthesis; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D014157:Transcription Factors / Q000096:biosynthesis*; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases
D004268:DNA-Binding Proteins; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D014157:Transcription Factors; D000070584:Tripartite Motif Proteins; C084523:TRIM25 protein, human; D044767:Ubiquitin-Protein Ligases