Abstract: Background and purpose: The prognosis of ovarian cancer is poor and the diagnosis is relatively late. It is needed to search for early diagnosis and treatment for ovarian cancer. This study investigated the expression of serum miRNAs in patients with malignancy or benign ovarian tumor preoperativey and analyzed its correlation with clinicopathological progress and prognostic features of epithelial ovarian cancer. Methods: Forty-eight miRNAs which have been reported to be related to ovarian cancer were ordered. The differential expression of 48 miRNAs in the serum of patients with malignant or benign epithelial ovarian tumors was detected by TaqMan low density array. The differentially expressed miRNAs were further confirmed by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR). The relationship between the expression level of selected miRNA and clinical clinicopathological factors, progress and prognosis were analyzed. Results: TaqMan low density array and further RTFQ-PCR showed that only miR-125b was significantly increased in 135 ovarian cancer patients as compared with 38 individuals with benign tumor. The expression of miR-125b was higher in early stage patients than that in advanced stage patients (P=0.039). The patients without residual tumor expressed more miR-125b than patients with residual tumor (P=0.013). The high level of miR-125b was signifi-cantly correlated with longer progress free survival (PFS) (P=0.003), but not correlated with overall survival (OS) (P=0.069). Conclusion: MiR-125b may play an important role in the pathogenesis of epithelial ovarian cancer and prognosis. It may be a potential gene to predict the recurrence of epithelial ovarian cancer, but the change of gene expression at different stages and its underlying mechanism need further research.

Key words: Ovarian cancer, MiRNA expression cards, MiR-125b, Prognosis