Long non-coding RNA NEAT1/miR-320b/MSI2 axis regulates cisplatin resistance in ovarian cancer

Abstract

IntroductionOvarian cancer (OC) frequently occurs in postmenopausal women and it has higher mortality rate. Accumulating researches proved that long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) involved in the progression of chemoresistance in human OC. Here, the study aimed to investigate the partial molecular mechanism of OC chemoresistance.Material and methodsThe levels of NEAT1 and microRNA-320b (miR-320b) were measured by qRT-PCR. Western blot was carried out to determine the protein levels that used in this research. Cell viability was identified via Cell Counting Kit-8 (CCK-8). Transwell assay was employed to determine migration and invasion. The relationship between miR-320b and NEAT1 or MSI2 was clarified by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and RNA pull down assay. Also, a murine xenograft assay was used to explore the effect of NEAT1 on cisplatin resistance in OC in vivo.ResultsThe level of NEAT1 was significantly increased in cisplatin resistant OC cell lines. Downregulation of NEAT1 enhanced cisplatin sensibility in OVCAR-3/DDP and HEY/DDP cells. Furthermore, miR-320b was a target of NEAT1, and the effects of knockdown of NEAT1 on the cell viability, IC50 of cisplatin, migration and invasion in OVCAR-3/DDP and HEY/DDP were restored by the inhibitor of miR-320. In addition, miR-320b directly targeted MSI2 to regulate cisplatin sensibility in cisplatin resistant OC cells. In addition, downregulation of NEAT1 decreased cisplatin resistance in OC in vivo.ConclusionsNEAT1 regulated cisplatin resistance through NEAT1/miR-320b/MSI2 axis in OC, which might offer a novel therapy target for the chemotherapy of OC.