Circ-ITCH correlates with small tumor size, decreased FIGO stage and prolonged overall survival, and it inhibits cells proliferation while promotes cells apoptosis in epithelial ovarian cancer.

Abstract

The aim of this study was to evaluate the correlation of circular RNA itchy E3 ubiquitin protein ligase (Circ-ITCH) expression with clinicopathological features and survival in patients with epithelial ovarian cancer (EOC), and to explore its effect on cells proliferation as well as apoptosis in EOC cells. Seventy-seven EOC patients underwent surgery were retrospectively reviewed. Tumor tissues and paired adjacent tissues samples were collected, and Circ-ITCH expression was evaluated by quantitative polymerase chain reaction (qPCR). Blank mimic, Circ-ITCH mimic, blank inhibitor and Circ-ITCH inhibitor plasmids were transfected into SKOV3 cells and OVCAR-3 cells, and Counting Kit-8 (CCK-8) was performed to assess cells proliferation and Annexin V (AV)/propidium iodide (PI) was conducted to detect cells apoptosis. Median value of Circ-ITCH relative expression was 0.697 (0.367-1.106) in tumor tissues, which was lower compared with paired adjacent tissues (1.690 (0.867-2.813)) (P< 0.001), and it negatively correlated with tumor size (P= 0.005) as well as International Federation of Gynecology and Obstetrics (FIGO) stage (P< 0.001) in EOC patients. Multivariate Cox's analysis revealed that high Circ-ITCH expression was an independent predictive factor for favorable OS in EOC patients. Moreover, further in vitro experiments disclosed that Circ-ITCH expression was decreased in several EOC cell lines compared with normal ovarian epithelial cell line, and it inhibited cells proliferation while promoted cells apoptosis in SKOV3 and OVCAR-3 cells. Circ-ITCH correlates with small tumor size, decreased FIGO stage and prolonged OS, and it inhibits cells proliferation while promotes cells apoptosis in EOC.