Nuclear survivin is associated with malignant potential in epithelial ovarian carcinoma

Abstract

Survivin is a unique member of the inhibitor of apoptosis (IAP) protein family. As abnormal inhibition of apoptosis during homeostasis is considered a critical step in the initiation of cancer, we investigated prognostic value of survivin expression in epithelial ovarian carcinomas. We carried out immunohistochemical experiments using a polyclonal antisurvivin antibody to stain formalin-fixed paraffin-embedded sections from 91 patients with ovarian tumors, including 10 cystadenomas, 17 borderline tumors, and 64 epithelial ovarian carcinomas. Nuclear and cytoplasmic survivin staining was scored separately. Survivin expression was undetectable in ovarian cystadenomas and was weakly detected in 4 of 17 (23.53%) borderline tumors. In contrast, nuclear and cytoplasmic survivin staining was observed in 55 of 64 (85.94%) epithelial ovarian carcinomas. Scoring on the basis of the percentage of survivin nuclear-positive cells indicated that nuclear survivin expression was associated significantly with clinical stage, histologic grade, proliferating cell nuclear antigen (PCNA)-labeling index, and clinical outcome in ovarian epithelial carcinoma patients (P<0.01). Taken together, the results of this study provide evidence that nuclear survivin expression is a strong, independent prognostic marker for poor clinical outcomes in epithelial ovarian carcinoma.