lncRNA UCA1 Mediates Resistance to Cisplatin by Regulating the miR-143/FOSL2-Signaling Pathway in Ovarian Cancer

The aim of this study was to explore the roles of the long noncoding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) on cisplatin resistance in ovarian cancer and the underlying mechanisms. We investigated the expression of lncRNAs in 3 paired cisplatin-sensitive and cisplatin-resistant tissues of ovarian cancer by microarray analysis. The qRT-PCR analysis was to investigate the expression pattern of UCA1 in cisplatin-resistant ovarian cancer patient tissues and cell lines. Then we examined the effects of UCA1 on cisplatin resistance in vitro and in vivo. In this study, UCA1 was observed to be upregulated in cisplatin-resistant patient tissues and cell lines. Knockdown of UCA1 inhibited cell proliferation and promoted the cisplatin-induced cell apoptosis in ovarian cancer cells. Then we demonstrated that repressed UCA1 promoted the miR-143 expression and miR-143 could bind to the predicted binding site of UCA1. Furthermore, we found that miR-143 displayed its role via modulating the FOSL2 expression. Importantly, we demonstrated that UCA1 was upregulated in serum exosomes from cisplatin-resistant patients. In summary, our study demonstrated that UCA1 modulates cisplatin resistance through the miR-143/FOSL2 pathway in ovarian cancer.