Expression of the plasminogen activator inhibitor-1 RNA binding protein (PAI-RBP1) in epithelial ovarian cancer (OC)

Abstract

9628 Background: The plasminogen activator-plasmin cascade plays a central role in tumor cell invasion and metastasis of solid tumors. The type-1 plasminogen activator inhibitor (PAI-1) is the major physiologic regulator of the plasminogen activation. The novel PAI-RBP1 is suggested to play a crucial role in cyclic nucleotide-mediated regulation of PAI-1 mRNA stability. The expression of PAI-RBP1 in OC is unknown. We are the first working group to analyse the expression of PAI-RBP1 in OC. Methods: Identification of overexpressed genes in OC by in-silico analysis (AUTEX, e-NORTHERN, BLAST). In a second step analysis of the expression of PAI-RBP1 by in-situ hybridization was performed. Tissue sections of paraffin-embedded tumor specimens from patients (pts) with benign and malignant ovarian tumors (OT), who underwent surgical intervention in the Department of Gynaecology and Obstetrics, Charité, from 02/01 to 06/02, were used. Correlation analysis with conventional clinical factors was performed by using SPSS (SPSS Inc., V.11,0; Chicago 2001). Results: 57 pts (28 primary OC, 15 recurrent OC, 3 low-malignant potential OT, 6 benign OT, 5 normal ovary) were allocated to this trial. Median age was 57 years (range, 34–86). Median follow-up was 20 months (range, 0–64). The distribution of tumor stage FIGO of all primary OC was: I=16.2%, II=3.2%, III=45.2% and IV=35.5%. PAI-RBP1 was significantly overexpressed in tumor epithelium of OC in comparison to ovarian epithelium of benign OT and normal ovary (p=0.002). In statistical analysis a significant correlation between the PAI-RBP1 expression and FIGO-stage was observed (p=0.014). Conclusions: PAI-RBP1 is significantly overexpressed in OC and correlates with the clinical tumor stage FIGO. Based on these results the prognostic role of PAI-RBP1 will be analysed. No significant financial relationships to disclose.