Long non-coding RNA opa-interacting protein 5 antisense transcript 1 (LncRNA OIP5-AS1) promoted cisplatin resistance in nasopharyngeal carcinoma via the miR-378a-3p/nicotinamide N-methyltransferase axis

LncRNAs involve in chemoresistance of human cancers. However, the role and molecular mechanisms of lncRNA OIP5-AS1 in the chemoresistance of NPC are still unexplored. In our study, upregulated OIP5AS1 was found in cisplatin (CDDP)-resistant NPC tumors and cell lines. Functional assays revealed OIP5AS1 knockdown suppressed malignant behaviors, but stimulated apoptosis of CDDP-resistant NPC cells. Furthermore, we demonstrated OIP5-AS1 positively regulated NNMT by directly targeting miR-378a-3p. In addition, its inhibition partially abolished the inhibitory effects of OIP5-AS1 silencing on malignancy of CDDPresistant NPC cells, whereas NNMT knockdown reverse these effects. In sum, our results indicated OIP5-AS1 contributed to the CDDP resistance of NPC by sponging miR-378a-3p to increase NNMT expression.