[Expressions of Cx43 and Skp2 in epithelial ovarian tumor and their clinical significances].
OBJECTIVE
Connexin 43 (Cx43), an important member of connexins family, is frequently down-regulated in neoplastic cells. It has been shown to have gap junction-dependent anti-tumor effect on various tumor cell lines. Recently, it was reported that Cx43 could inhibit tumor growth via down-regulating the expression of S-phase kinase associated protein 2 (Skp2). Skp2, a member of F-box protein family, can specifically recognize, and accelerate the ubiquitin-mediated degradation of several key regulators of G(1) phase progression. This study was to detect expressions of Cx43 and Skp2 in epithelial ovarian tumor, and to explore their correlations to tumorigenesis and development of ovarian cancer.


METHODS
Expressions of Cx43 and Skp2 were examined by immunohistochemistry in 81 specimens of epithelial ovarian tumor (13 specimens of adenoma, 12 specimens of borderline adenoma, and 56 specimens of adenocarcinoma). Relationship between expression levels of Cx43 and Skp2, and association of their expression levels with clinicopathologic factors were statistically analyzed.


RESULTS
Positive rates of Cx43 in ovarian adenoma, borderline adenoma, and ovarian adenocarcinoma were 84.6% (11/13), 66.7% (8/12), and 33.9% (19/56), respectivelyu expression level of Cx43 in ovarian adenocarcinoma was significantly lower than those in ovarian adenoma (P<0.01), and borderline adenoma (P<0.01). Positive rates of Skp2 in ovarian adenoma, borderline adenoma, and ovarian adenocarcinoma were 0, 0, and 46.3% (26/56), respectivelyu expression level of Skp2 in ovarian adenocarcinoma was significantly higher than those in ovarian adenoma (P<0.01), and borderline adenoma (P<0.01). Moreover, the expression levels of Cx43 and Skp2 were independent of age and histological type, but significantly associated with pathologic grade, clinical stage, and positive lymph node metastasis of ovarian adenocarcinoma. Besides, in ovarian adenocarcinoma, expression level of Cx43 was moderately inversely correlated with that of Skp2 (r=-0.48, P<0.01).


CONCLUSIONS
Down-regulation of Cx43, and over-expression of Skp2 are tumor specific, and may play important roles in tumorigenesis, and development of ovarian cancer. Up-regulation of Skp2 may be related with down-regulation of Cx43 in ovarian cancer.
Hu
Ye-Qing
YQ
Department of Gynecology and Obstetrics, People's Hospital, Wuhan University, Wuhan, Hubei 430-060, P.R. China. leafgreen@tom.com
Liu
Yuan-Jiao
YJ
D000328:Adult; D000368:Aged; D018269:Carcinoma, Endometrioid / Q000378:metabolism / Q000473:pathology; D018031:Connexin 43 / Q000378:metabolism*; D018282:Cystadenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology; D018284:Cystadenocarcinoma, Serous / Q000378:metabolism* / Q000473:pathology; D018291:Cystadenoma, Mucinous / Q000378:metabolism / Q000473:pathology; D018293:Cystadenoma, Serous / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology; D011230:Precancerous Conditions / Q000378:metabolism / Q000473:pathology; D044786:S-Phase Kinase-Associated Proteins / Q000378:metabolism*
D018031:Connexin 43; D044786:S-Phase Kinase-Associated Proteins