Overexpression of c-IAP1 , a Member of the Inhibitor of Apoptosis , Identified by cDNA Microarray Technique in Ovarian Carcinomas

Cho, C H; Lee, T S; Cha, S D; Baek, W K; Seo, S I; Seo, M H; Park, K G; Jung, N C; Bae, I S; Kwak, J S

Abstract

OBJECTIVE
Programmed cell death or apoptosis is a fundamental event in the developmental and homeostatic processes of all multicellular organisms. In this study, we preliminarily evaluated comparative patterns of gene expression between ovarian carcinoma and normal ovary by cDNA microarray analysis[Clontec Laboratory, Inc.]. We identified the overexpression of c-IAP1 in ovarian carcinomas compared with normal ovary. This finding was obtained using RT-PCR [Reverse Transcriptase Polymerase Chain Reaction] and immunohistochemical stains in large scale.
METHODS
Twelve epithelial ovarian carcinoma tissues, 5 normal ovarian tissues from benign gynecologic disease and 2 benign ovarian tumors were examined for the presence of c-IAP1 by RT-PCR and immunohistochemical stain.
RESULTS
All cases of ovarian carcinoma tissues were positive and 2 normal ovarian tissues were negative for c-IAP1 by RT-PCR assay. Two of 5 positive normal ovarian tissues were weakly positive compared with positive ovarian carcinoma tissues. The source of the c-IAP1 expression was further examined by immunohistochemical studies. c-IAP1 was detectable in all ovarian carcinoma tissues which were positive by immunohistochemical staining. Expression of c-IAP1 in normal ovarian tissue was localized exclusively in the corpus luteum. There was no expression in normal ovarian stroma cells for c-IAP1 protein.
CONCLUSION
These findings suggest that c-IAP1 is produced by ovarian tumors in vivo and that association between antiapoptosis and tumor generation may be clinically relevant. Expression of c-IAP1 in corpus luteum suggest that may be involved in ovarian follicular development and atresia.