Circular RNA circMYBL2 regulates the progression of ovarian cancer through miR-195-5P/BIRC5 axis.

Ovarian cancer has emerged as the most malignant gynecological tumor, primarily due to the challenges associated with early diagnosis. The majority of patients are diagnosed at an advanced stage, and the disease exhibits a high recurrence rate within three years following comprehensive treatment. Consequently, there is an urgent need to identify reliable prognostic indicators and therapeutic targets. Circular RNA (circRNA), characterized by its stable circular structure, demonstrates greater stability than mRNA within cells. It plays a significant role in regulating the initiation, progression, and chemotherapy resistance of various tumors, making it a promising candidate for novel therapeutic targets. However, a comprehensive understanding of the expression and functional mechanisms of circRNA in ovarian cancer remains elusive. In this study, we identified that circMYBL2 (hsa_circ_0060467) was significantly upregulated in ovarian cancer tissues and cell lines. Functionally, circMYBL2 was found to promote the proliferation, invasion, and migration of OVCAR3 and CAOV3 cells in vitro. In vivo experiments demonstrated that knockdown of circMYBL2 inhibited the growth of CAOV3 cells, an effect that was reversed by the overexpression of BIRC5. Mechanistically, circMYBL2 functions as a molecular sponge for miR-195-5p, upregulating BIRC5 upon binding to miR-195-5p, thereby facilitating the proliferation, invasion, and migration of ovarian cancer cells. These findings indicate that circMYBL2 contributes to ovarian cancer progression through the circMYBL2/miR-195-5p/BIRC5 axis. As such, circMYBL2 may serve as a novel diagnostic marker and a potential therapeutic target for ovarian cancer. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13048-025-01946-2.