LncRNA RAD51B-AS1 promotes the malignant biological behavior of ovarian cancer via upregulation of RAD51B

Background Ovarian cancer (OC) has the highest fatality rate amongst all gynecologic malignancies. Exploring new factors and pathways associated with development of ovarian cancer would help to identify new therapeutic targets. Long non-coding RNAs (lncRNAs) play indispensable roles in the process of the progression of OC. Methods Reverse transcription-quantitative PCR (RT-qPCR) was performed to verify the expression of RAD51B-AS1 in cell lines and patients’ tissues. Cellular proliferation, metastasis and apoptosis were detected using Cell Counting Kit-8(CCK-8), colony formation, Transwell and flow cytometry assays, respectively. Mouse xenograft models were established to detect tumorigenesis. RT-qPCR, western blotting and immunofluorescence experiments were conducted to explore the quantitative and positional relationship between RAD51B-AS1 and its host gene, RAD51B. Co-transfection rescue experiments were then performed to preliminarily explore its mechanism in vivo and in vitro. Results RAD51B-AS1 was significantly upregulated in a highly metastatic human OC cell line and in OC tissues. RAD51B-AS1 significantly increased the proliferation and metastasis of OC cells, whilst also enhancing resistance to anoikis. Biogenetics prediction analysis revealed that the only target gene of RAD51B-AS1 was RAD51B. Subsequent gene function experiments revealed that RAD51B exerted the same biological effects as RAD51B-AS1. Rescue experiments demonstrated that the malignant biological behaviors promoted by RAD51B-AS1 overexpressing were partially or completely reversed by RAD51B silencing in vitro and in vivo.Conclusion RAD51B-AS1 promoted the malignant biological behavior of OC, and the underlying mechanism of this action may be associated with the positive regulation of RAD51B expression. The present study revealed a potentially novel molecular mechanism underlying the development of OC. RAD51B-AS1 is expected to serve as a novel molecular biomarker for the diagnosis and prediction of a poor prognosis in OC, and as a potential therapeutic target for management of the disease.