Long non-coding RNA SOX2OT promotes cell proliferation and motility in human ovarian cancer

Ovarian cancer is one of the most common malignant gynecological cancers. Although conventional chemotherapies have improved the treatment of patients with ovarian cancer, the mortality rate remains high. Hence, it is crucial that the detailed mechanisms that promote ovarian cancer are urgently identified. Therefore, reverse transcription-quantitative polymerase chain reaction was used to reveal the relative transcript levels. Colony formation assay and cell cycle assay were performed in siRNA-treated cells. Transwell assay and western blot assays were also conducted. The results showed that the expression of long non-coding RNA SRY-box 2 overlapping transcript (SOX2OT) was upregulated in clinical ovarian cancer tissues and in cultured ovarian cancer cells (HO-8910 and HO-8910PM). High expression of SOX2OT negatively correlated with the prognosis of patients with ovarian cancer. Knockdown of SOX2OT by specific small interfering RNA against SOX2OT suppressed the colony formation capacity of invasive ovarian cancer cells and resulted in cell cycle arrest in G0/G1 phase. Key cell cycle regulators, cyclin B1 and cell division cycle 25C, were consistently downregulated by the knockdown of SOX2OT. Furthermore, knockdown of SOX2O Tinhibited cell migration, cell invasion and decreased the expression of mesenchymal protein N-cadherin, whereas the expression of epithelial protein E-cadherin was increased in ovarian cancer cells. Overall, SOX2OT expression levels correlated with the prognosis of patients with ovarian cancer, and SOX2OT promoted cell proliferation and motility in ovarian cancer cells. These findings indicated that SOX2OT may serve as a potential therapeutic target in the treatment of ovarian cancer.