LncRNA HOTAIR Regulates CCND1 and CCND2 Expression by Sponging miR-206 in Ovarian Cancer

Background/Aims: The long noncoding RNA homeobox (HOX) transcript antisense intergenic RNA (HOTAIR) has been demonstrated to be a vital modulator in the proliferation and metastasis of ovarian cancer cells, but its potential molecular mechanism remains to be elucidated. In the current study, we aimed to uncover the biological role of lncRNA HOTAIR and its underlying regulatory mechanism in the progression and metastasis of ovarian cancer. Methods: HOTAIR expression was detected by quantitative RT-PCR (qRT-PCR) and northern blotting. The SKOV3 ovarian cancer cell line was chosen for the subsequent assays. In addition, the molecular mRNA and protein expression levels were examined by qRT-PCR and western blotting. The competitive endogenous RNA (ceRNA) mechanism was validated by bioinformatics analysis and a dual luciferase reporter gene assay. Results: HOTAIR expression was significantly higher in ovarian carcinoma tissues and cell lines than in the control counterparts. Both CCND1 and CCND2 were downstream targets of miR-206. The inhibition of HOTAIR elevated the expression of miR-206 and inhibited the expression of CCND1 and CCND2. Moreover, CCND1 and CCND2 were highly expressed in ovarian cancer tissues, and their expression was positively correlated with HOTAIR expression. Finally, the functional assays indicated that the anticancer effects of miR-206 could be rescued by the simultaneous overexpression of either CCND1 or CCND2 in ovarian cancer. Conclusion: HOTAIR enhanced CCND1 and CCND2 expression by negatively modulating miR-206 expression and stimulating the proliferation, cell cycle progression, migration and invasion of ovarian cancer cells.