Abstract: Circular RNA (circRNA), a novel class of long noncoding RNAs, is characterized by a covalently closed continuous loop without 5′ or 3′ polarities structure and have been widely found in human bodies. CircRNA is more stable than liner RNA. It has better tissue specificity and the expression levels in normal tissue and tumor tissue are different. Its molecular biological functions especially the microRNA(miRNA) sponge make it possible to act as the new tumor biomarker and the new target for targeted therapy. Recent studies have revealed that circRNA plays an important role in tumorgenesis, early diagnosis, therapy, prognosis, radiosensitivity and chemosensitivity in malignant tumors. However, the research on the function and regulation machanism of circRNA in ovarian cancer is still in the initial stage and rare at present. This article reviews the researches on the molecular biological characteristics and functions of circRNAs in ovarian cancer.

Key words: RNA, MicroRNAs, Ovarian neoplasms, Circular RNA