Introduction/Background Ovarian cancer is really considered to be the fifth most common cause of cancer death among women and the most lethal form of gynecological malignancy. CD24 is a small,cell-surface sialoglycoprotein and an independent marker for poor prognosis in different type of cancers.

Methodology Our aim was to determine the expression of CD24 in ovarian tissue, plasma, and exosome samples of patients with serous ovarian cancer.

Tissue and blood samples were collected from 21 serous ovarian cancer patients and from 8 healthy controls. RNA was isolated by silica adsorption method, cDNA was synthesized and quantitative real-time PCR was performed. Beta-globin was used as housekeeping gene for the normalisation of the data. Protein-protein and miRNA networking was analysed by using Biogrid and miRTargetLink databases.

Results Significant difference (p=0.007) was determined in expression of CD24 in ovarian tissue samples between controls (0.16±0.32) and patients (44.97±68.06), while CD24 was not expressed in all plasma and exosome samples. Correlation was observed in expression of CD24 and FIGO grading between controls and patients.

Based on network analysis, the LYN, SELP, FGR and NPM1 proteins showed interaction with CD24.

Conclusion Higher expression of CD24 was determined in ovarian cancer patients‘ tissue samples and showed an association with FIGO classification. However, CD24 was expressed in just some cell-free plasma and exosome samples.

Disclosure Nothing to disclose.