MiR-34a Inhibits Cell Proliferation and Induces Apoptosis in Human Nasopharyngeal Carcinoma by Targeting lncRNA MCM3AP-AS1.

Introduction: MCM3AP-AS1 has been characterized as an oncogenic lncRNA in several types of cancer, while its role in nasopharyngeal carcinoma (NPC) is unknown. This study aimed to investigate the role of MCM3AP-AS1 in NPC. Patients and Methods: Paired NPC tissues and non-tumor tissues were collected from 55 NPC patients. Expression of MCM3AP-AS1 and miR-34a in paired tissues was analyzed by RT-qPCR. Interactions between MCM3AP-AS1 and miR-34a were analyzed by over-expression experiments. The roles of MCM3AP-AS1 and miR-34a in regulating NPC cell proliferation and apoptosis were explored by cell proliferation assay and cell apoptosis assay, respectively. Results: Our bioinformatics analysis showed that MCM3AP-AS1 may be targeted by miR34a, which is a well-studied tumor suppressor miRNA. In this study, we showed that miR34a was downregulated and MCM3AP-AS1 was upregulated in NPC. An inverse correlation between the expression of MCM3AP-AS1 and miR-34a was found across NPC tissue samples. High expression level of MCM3AP-AS1 and low levels of miR-34a in NPC tissues predicted the poor survival. In NPC cells, overexpression of MCM3AP-AS1 did not affect the expression of miR34a, while overexpression of miR-34a led to downregulated MCM3AP-AS1. Cell proliferation and apoptosis assay showed that overexpression of miR34a reduced the enhancing effects of overexpressing MCM3AP-AS1 on cell proliferation and the inhibitory effects on cell apoptosis. Conclusion: MiR-34a inhibits cell proliferation and induces apoptosis in human NPC by targeting MCM3AP-AS1.